it's really hard to do on firefox, but if u happen to get it infected somehow with a virus, u hafta reinstall it. normally, with IE i was able to just heal it somehow, with firefox it becomes such a pain. LOL right now i have this message that comes up, and then it says that it creates a problem and firefox has to shut down. haha, its really hard to do tho on firefox. also, u cant view certain stuff, like parts of MTV.com and any other page that requires IE 5.0 or whatever those flash sites need. But yea, i use it as a primary browser. i love it.