I found GamingLagoon through a Squidoo Lens and eventually joined it at GPTCashcow. GamingLagoon gives 0.25 points for referrals AND it's international, so it's one of the easiest sites to promote a gain a huge collection of referrals if you want to.
Don't want to do that? Then, there's daily surveys, offers(free and Credit Card), and daily "hot offers" that do have an earning cap. Get enough points and you can get a SLEW of prizes. Everything from hosting to Wii/Xbox things.
Right now, there's a contest running from May 20th-May 24. The way it works is that for every ten offers you do, you get $1.00 on May 25th AND an entry to win a FREE Nintendo Wii OR a Nintendo DSi.
You DO have to verify your account by letting them call you and a leave a voice message containing the info that they want, but this is how they weed out cheaters/scams, so it's not something that bothers me too much. Takes maybe 5 minutes to do, but can take up to 48 hours to actually BE verified. However, it didn't take long for my account to be verified at all, so it's not too big a deal.
Beyond that, Gaming Lagoon is one of the better Dietzel sites in the network and one of the more popular GPT sites out there if you just wanting gaming stuff, url hosting, and prizes unique to the "Lagoon Group".