BREADBOX64, a twitter client for the C64. (via Waxy)
With BREADBOX64 you can post status messages and view your friends timeline. The timeline refreshes every two minutes. After starting you provide your twitter username and password separated by a colon. After pressing enter, the timeline is retrieved and shown. At the bottom of the screen there is an input field for you to type aq status message. Pressing enter will post that message to twitter.
You can run BREADBOX64 on a C64 emulator. I use VICE, because that one supports networking. However, you can better test it on a real system if you have the hardware ready at hand. If so, copy the D64 to a real disk, put it in your 1541 and go ahead!