If you’re using a good or awesome operating system (and actually anything other than windows), you can post to Twitter using their API. Just use the great and powerful curl.
Open up your Terminal or Command Line (whatever you want to call it) and type:
curl -u email:password -d status=”your message here” http://twitter.com/statuses/update.xml
You must insert your Email and Password in the instruction, obviously.
Read more about this: here!