Thank you Zach Margolis for posting a page on his del.icio.us about using Twitter's API to update it from the command line. For some reason, just the thought of opening a terminal and posting to my blog is appealing to me... I hate you Zach Margolis.
curl -u yourusername:yourpassword -d status="Your Message Here" \
Then set up an alias so you just need to type something like:
t "Your Message Here"
And you'd be all set.