I’m not usually big on minimizing apps to the system tray … I’ve already got far too many icons down there. But this one does a couple of things that I find to be really handy: it keeps Firefox resident, even if I’m not running it at the time (and if I’m not running Firefox now, you can bet I will be within the next 10 minutes). It also allows me to start Thunderbird, have it minimize to the tray and announce when I’ve got new mail. Both of these are good things for me.
To make this all work, go here and don’t forget to click on the Installation link at the top of the page to get all the details on what you need to do. Not a lot of work but a tiny bit more than usual.