While I have covered 16 interesting things that you can do with Twitter, it only covered the tip of the iceberg. Ever since Twitter released their API, there are really thousands of things that you can do with it – one of them is to track your FedEx, UPS, USPS and DHL shipment with Twitter.
TrackThis is a Webservice that monitors your package shipment for you. To get started, simply follow TrackThis at http://twitter.com/trackthis and wait for it to follow you back. Once that is done, you can send your shipment tracking code via a direct message to TrackThis.

The syntax to use is [tracking code] [nickname of package]. For example, if you ordered a PC and the tracking code from FedEx is 1234567, send:
d trackthis 1234567 PC
Trackthis will then reply you with a direct message each time your package changes location.
If you know of any other interesting applications with Twitter, do let just know.
[via CyberNet]
While most of us are used to moving mouse and clicking around the screen, sometime things can be done faster if you use the preset shortcut keys. Similarly, for those who spent a lot of time in your Gmail, the following shortcut keys will definitely be of great use to you.
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If you are a frequent user of Facebook, Twitter, AIM, Flickr, FriendFeed, Youtube and wish there is a centralized place to control everything, now you have it –