Not exactly free but... Warhammer Online just launched a new free trial with no time duration. you can play for as long as you like, with as many classes as you like from either faction. you can participate in the game fully; the catch is they cap you off at level 10 (which is a good place to be in terms of tier1 pvp).
Mythic Entertainment | Warhammer Online ? Play the Free Trial!
* Also, they have a new streaming client which is much smaller than typical mmo's of our day to install, it just downloads as necessary so will end up being a lot smaller install (a couple gig instead of several).