Fantasy Web Comics

[MonsterMash]

I don't read that many but Order of the Stick and Dork Tower are still favourites.

Not fantasy, but with occasional RP and Cthulhu Mythos related jokes User Friendly

 

[Krug]

Tales of the Traveling Gnome is looking pretty good.

 

[Krug]

Another one that looks pretty good. Drow Tales.

 

[fett527]

I read Critical Fumble as well as others mentioned here. It's by David Nicklaw and he uses the sprites from the old stand-up D&D game.