Birdy 1.0

For heavy-duty Twitterers, it would be hard to give up the highly useful Twhirl, but just for fun there is now Birdy 1.0. This AIR app is a little blue bird that sits on your desktop and (literally) tweets your Twitter updates.

TrackThis

One of the more useful Twitter apps to date, TrackThis helps you track your packages with Twitter’s help. TrackThis supports FedEx, UPS, USPS, and DHL. To use TrackThis, first follow Twitter user @trackthis. Then send a DM to TrackThis with the Tracking code and brief description of the package.

Example: 12345689123 New PC

That’s it! You don’t even have to specify which service is being used, TrackThis figures it out. Each time your package changes locations, you’ll receive a DM.

(Donations accepted)

Twitimonials

Recommend your Twitter friends with Twitimonials. This service lets you tweet about other tweeters and have what you say tracked on their homepage. To use Twitimonitals, follow Twitter user yitu (Why I Twit You) and then post your tweet in the following format: @yitu @friendname and whatever you want to say.

Twist

From the same people who brought you the Twitter search engine there now comes Twist, a service for tracking trends in Twitter. At Twist, you can compare various keywords against each other and see them charted before your eyes.

Twictionary

Trying to learn all the Twitter lingo? Twictionary can help. The site, a PBWiki, keeps track of the "English language as used on Twitter." Sample words include "tweeps," "tweetup," and "twat."

SalesTwit

CRM for Twitter. Sign up at SalesTwit then load your sales leads into SalesTwit. Whenever you have a spare minute, you can ask SalesTwit, via Twitter, to send you your next lead. SalesTwit helps sales professionals when they have time to kill by making those spare minutes productive.

TopTweet

The Twitter app TopTweet lets you stay up-to-date on all the best Twitter users and what they are tweeting. A good starting point for Twitter newbies who are looking for some friends to follow.

TwittEarth

Like TwitterVision is to Google Maps, TwittEarth is to Google Earth. In other words, way better. This mashup shows tweets around a spinning globe. Pure eye candy.

TweetLater

Another auto-tweeting service, TweetLater lets you schedule future tweets and even auto-response and auto-follow your new followers.

twittersearch.flaptor.com

What kind of name is that? The site at twittersearch.flaptor.com aims to be a Twitter search engine, which lets you search Twitter in real-time.