Firefox/Chrome/Internet Explorer: Tweetfilter is probably the most powerful filter you can find for your Twitter stream, unless you start decoding Twitter’s API yourself. You can block phrases, retweets of certain users, particular web sites and services and nearly anything else.
Firefox with Greasemonkey: User script Gmail Labels Icons extends the Gmail label customisation from just colours to icons as well, so you can more easily tell your folders apart with a visual clue.
Google Calendar recently updated their favicon to a calendar page with a number on it, though the number doesn’t change. With a simple user script, though, you can make it display the current date.
Firefox/Chrome/Safari: If Facebook’s a little too cluttered for your taste, the Minimalist Facebook extension/Greasemonkey script can tidy things up. After a quick install, a visit to Facebook will be focused solely on the content you’ve chosen to view.
Firefox with Greasemonkey: During Gmail’s latest design upgrade, the multiple selection links, including the “Unread” selector, were moved into an integrated box. Gmail fiends like Matt Kruse loved that “Unread” link, so he created a Greasemonkey script that brings them back.
Most Browsers (Greasemonkey): If your Facebook News Feed is still clogged with annoying applications and unimportant updates, simple user script F. B. Purity can seriously narrow it down to just the important stuff.
