Poker Champs was #1, except their freerolls are down while they improve the connectivity problems thay've had on their site. Money games are still available. They had 5 freerolls a day, in the middle of the night in the US (which is good for me), and they were turbos.
Absolute Poker #2, though 2000 people in a game can be daunting (though that's better than 6000 at Poker Stars).
Check n' Raise Poker #3, as they are small and the graphics are clever. I wish they had more freerolls and had one later in the evening.
I like all of the above because you don't have to make a deposit to play, and you get paid in money you can use to buy into tournaments on the site without making a deposit.
I resent True Poker for paying their Newbie Freerolls in dollars you can't use for tourneys until you've made a deposit--a system similar to the bogus Pending Bonus Dollars on Ultimate Bet. Some freerolls that fill up real fast, Pacific rings a bell, are a pain as I don't have DSL. Some freerolls like Royal Vegas and 333 are just at times of day I never play.