So firefox holds 20% of the browser market share (at least it did the last time I checked). And what makes firefox a browser of choice of tech-savvy users and people who are sick of IE? Extensions. SO my choices are: Blockers Adblock Plus -Blocks ads. duh. UPD: (Thanks to Apocrypha for that) : Adblock Plus subscriptions - Not exactly a Firefox extension, subscribe to these lists. It updates the ad filters of Adblock Plus every few days. You know, new banner networks etc. pop up every day, block'em all. Flash Block - well, It blocks flash. On old comps it can be pretty tough with sites bloated with heavy flash. Or on old comps with *nix OS's. (damn you, Adobe, give us a good flash plugin). And it doesn't block it completely, it just adds a button on top of blocked flash, when u press it - flash plays. Bug Me Not - An incredible time saver. Hate to register at some unknown site? Just use bug me not, it will automatically fetch a login and password from it's user driven database and login for ya. You most likely won't be able to login with it's help on paid membership sites though. Security NoScript - a ...