Let’s have some Firefox 2.0 plugins.
Deepest Sender , a Livejournal client. Better than SeMagic, although not as many features. Works great with the spellchecking.
del.icio.us bookmarks – becoming more and more synchronised with Firefox over time; earlier versions just slapped a couple of buttons on the menu, but this now auto-uploads your bookmarks, keeps track of them all on multiple machines, & replaces them with dynamic toolbars (e.g. all those tagged with ‘work’) – amazing, even if you only have the one computer.