Turn Firefox into a web writer: Here’s a great article over at Lifehacker on how to hot-rod Firefox into being a really nice place to write text. We’ve probably covered all these extensions at one time or another, but it’s really handy to have all this one place. You can pimp a textarea quite a bit with the right extensions.
My new favorite: Tabinta, which let’s you insert tabs in textareas. Web developers have to write HTML in textareas way too often to not have this plugin.