Below are other websites that interact with Twitter

This is my number one application to use- Tweetdeck!
http://www.tweetdeck.com/TweetDeck enables users to split their main feed (All Tweets) into topic or group specific columns allowing a broader overview of tweets. The default columns can contain All Tweets from your timeline, @replies directed to you and direct messages.

Contact Management

TweetBeep – Google Alerts meets Twitter. Great service that notifies you whenever your name (or any other word you specify) is mentioned. Use it to catch @replies that might have been missed, for reputation management, or customer support (you’d be surprised how many people vent their frustrations on Twitter).

GroupTweet – Great tool to use if you want to send public tweets simultaneously but only to a select group of people. For instance: sending notifications to your web development team or special updates to members of your family

.DoesFollow? – Find out if who if the person you’re following is following you back.

FriendOrFollow – Gives you breakdown of a) those you follow who do the same, and b) a list of those you don’t follow but follow you.

Twubble – Want to find more Twitter peeps to follow? Twubble is a sweet site that searches through your “friend graph” to get an idea of your current social network. It then returns a visual list of those who you might consider following based on that information

.Tweet2Tweet – Allows you to view a conversation in a much easier fashion

Twollow- Automatically follow members based on keywods in their tweets.
Custom Backgrounds

http://www.twitterbacks.com/ – Ready to get a better Twitter background going? Go ahead and download the files below and construct your own Twitter background. I have yet to do that.

twitibacks
http://www.paintermommy.com/

Twitter Searches

Twitter Search (formerly Summize) – Hands down, one of the best tool for finding Twitter conversations and conducting niche/keyword research.

Twitscoop – Real-time current events for Twitter. Use it to research the latest trends and to find out what’s the hottest buzz… Also has a nifty tag cloud feature that’s quite useful.

Twellow – A great Twitter directory… Fantastic way to connect with others in you niche and industry. Also links to other social networking profiles such as Facebook and LinkedIn. P.S. Don’t forget to add your profile as well.

Just Tweet It – Another cool directory. This one allows you to be notified of new additions to your particular niche/industry category. Great for connecting with like-minded individuals

Twitterholic – Showcases the top 100 Twitter users. Test out your reverse engineering skills by following with these Twitter rockstars and find out what they’re doing to gain followers and increase their visibility.
Status Updaters

Ping.fm – Update Twitter and a plethora of social networking sites such as Myspace, Facebook, and Pownce at the same time… Wonderful time saver!

Hellotxt – Another good status updater for your social networking.
Creative Ideas

TwitPic – Easily post your photos and share them on Twitter.

TwitSay – Record a 10 second voice message and share it with your Twitter peeps. Use it as a quick and creative way to engage your followers, especially when you can’t text or don’t have access to a computer

TwitHire – A free job listing board. Employers can promote their employment opportunities to social savvy job seekers… One of the most unique uses of Twitter I’ve seen.

Straw Poll – Need to get feedback? Create a poll and solicit responses just by tweeting… Cool interface, too!

.Twitter Keys – Have you ever seen icons and shapes in someone’s tweets? You might’ve even sent some yourself. Well, this cool site provides you with a bookmarklet that you can drag to your bookmarks toolbar. Click it to reveal a nifty, little popup with plenty of characters and icons you can use to spice up your tweets and make them stand out.

TwittyTunes – If you’re using the FoxyTunes plugin for Firefox, you can use TwittyTunes to easily tweet about the song you’re jamming to online. You can also share the sites you’re viewing, and videos you’re watching.

URL Shorteners

Snip URL – As I’m sure you know, Twitter doesn’t lend itself well to the long-winded. With only 140 characters at your disposal, shortening long website addresses is a must. Snip URL is one of the best in the game, in my opinion. You can create an account, easily share your links, and even view unique clicks (something many similar sites don’t offer).

TinyURL – One of the most popular URL shorteners around. Also has a bookmarklet you can drag to your bookmarks toolbar… Allows you to create shortened URLs with a single click.

is.gd – With only four letters (and a dot), is.gd is great for URL shortening.
Account Management and Notifiers

TweetTake – Backup your followers, favorites, or just your entire Twitter account. Why? Remember the Twitter crash of Black Thursday (back in July 2008 when scores of users lost followers overnight)?

Twitterless – Service that sends you a DM (direct message) when you lose a follower.

Qwitter – Another services that sends you a notification when someone stops following you. This one sends you an email instead of a DM. Caveat: I think the jury is still out on these services. There might be legitimate reasons someone stops following you (e.g. they’re “following” you more on Pownce or Facebook). Or, there might not be a reason at all. However, this servicemight be good to use if you’ve been losing followers and want to find out why. Perhaps, you’re adding more noise than value. Maybe you tweet entirely too much. Regardless, use at your own discretion. Personally, I wouldn’t recommend confronting the person who un-followed you. Use this tool for research, not battle. (Make love, not war.)
Stats, Metrics, and Tracking

TweetBurner – Another essential service to add to your Twitter toolbox. This service lets you track the links that you share on Twitter… Also acts as a URL shortener.

Grader for Twitter – A tool that grades your relative reach and influence on Twitter. It also suggests a few people you should follow based on your profile.

Twitter Counter – Simple to use site (just plug in your Twitter name) and get stats that span a week. Use it to chart your progress in acquiring followers. Also offer a chicklet counter that can be added to your website or blog.

TweetStats – Add this stats tool to the essentials pile. This site offers detailed stats of your tweets, who you sent them to the most and when you usually sent them… Very nice breakdown of data.

twInfluence – Great tool for measuring the reach of your account and your entire network… Measures metrics like your “velocity” and “social capital.”

Hashtags – A service that lets you tag your posts as a way to group and organize them with others.

TwitterTise – Brand advertising meets Twitter… Track your links and measure their effectiveness.

Randoms

http://www.tweetlater.com/ – Keep your Twitter stream ticking over with new tweets even when you’re not in front of your computer. Or, use it as your personal reminder system.
PLUS… Send automated thank you notes to new followers, and automatically follow new followers, if you choose to do so. Schedule future-dated tweets!

http://tinyurl.com/3zz9mq – Looking for more people to follow? Twubblecan help expand your Twitter bubble—it searches your friend graph and picks out people who you may like to follow.

http://tinyurl.com/5r8abw -This is a good site to use during the Holidays. Today we are tweetering Helloween icons… oops I meant Halloween icons! You’ll see that I’ve had a lot of fun today with this site

http://www.twhirl.org/ – twhirl is a desktop client for social software such as Twitter, Friendfeed, identi.ca, or seesmic.

Twitterrific – is a fun application that lets you both read and publish posts or “tweets” to the Twitter community website. The application’s user interface is clean, concise and designed to take up a minimum of real estate on your Mac’s desktop.

http://tinyurl.com/3nbabf – Free Social Media Marketing Kit with Video and EBook. Learn How to Leverage Social Media for Your Business with this Social Media Marketing Kit.

http://twitter.com/downloads – Twitter lets you find out what your friends are doing in whatever way makes the most sense for you. Check out these downloads for other ways to send and receive Twitter Updates.

http://tinyurl.com/5d5eyd – Twitter Keys is a small tool, which provides you with a floating window with all these funny symbols you can use in Twitter.

http://splitweet.com/ – Multi Account Management for multiple twitter accounts , Corporate users, and brand monitor. All your Twitter accounts in one place, follow your contact’s tweets easily, monitor your brand & reply.