LookUP Tweets
I know I seem to mention LookUP a lot but I'm quite proud of it and it keeps improving. I made it as a meta service which looks through Simbad, NED, Skybot etc. in an attempt to find any astronomical object by name rather than just a subset of the Universe.
Now Rob Simpson has made use of the XML output to add LookUP on Twitter. If you have a Twitter account you can send a message of the form: "@lookupastro Mars" and it will reply back to you with the coordinates (Right Ascension and Declination) and a link to more info. Of course it is probably quicker to just use LookUP online, on your iPhone or normal phone but what Rob has done is very neat.