Freeroll poker tournaments are the smart gamblers way to win free money.  Many online poker sites offer freerolls that is open to all players without any requirements. Other sites require a number of player points or raked hands in order to qualify for the event.
Not only is a freeroll free to enter you also have a much better chance to succeed than in most other tournaments. Most players will not play their best game in a freeroll, because it’s free to enter they feels like they can take more chances than they normally would. So if you are patient, and focused your chances to finish in the money are very good. Everybody will play very loose in the first rounds, some will go all in with almost any two cards so you have to play tight and absolutely no bluffing, it’s very easy to call when you feel that you have nothing to loose.
Also you do not have to compete with the best players in a freeroll. Even if it’s free to play, the expected earnings per hour is to low for most good players. They make more money playing cash games or playing a tournament with a big buy in.
If you want to play freerolls you have to open a real money account and deposit at least the minimum , but after that you can play for free and win real money.
 

Most poker site have freerolls but here are some of the best:

Ladbrokes poker are one of the best sites for freerolls. Ladbrokes runs daily $1000, $500 and multiple $100 freerolls without any requirements. They also runs a $50000 freeroll with poker points buy inn. ( Ladbrokes are licensed in EU not open for US players )


Full Tilt Poker runs $100 freerolls every couple of hours and Sit and Go freerolls for seats in bigger tournaments.


Absolute Poker - Their freerolls are small often $50 prize pot but they are very frequent with 15 per day, one an hour at peak times.