If you’re using Google Chrome, and you’re running the developer version that allows extensions to be installed, you can now install TwitterBar for Google Chrome.
After you’ve installed it, just click on the Twitter icon in the toolbar bar, type your message, and press Enter to post your message to Twitter. (You’ll have to authorize TwitterBar the first time you tweet, but it only takes a second.)
If your message gets too long (Twitter only allows 140 characters), the happy blue Twitter bird will turn into an angry red Twitter cardinal.
Let me know what you think; I tried to keep as much of the functionality from the Firefox version as possible.