There is this site called Want want WANT IT that opened up a few months ago and they have been giving away cool tech like a Kindle Fire and Lenovo tablet. Now they are giving away a Galaxy Nexus 16 GB and Unlocked and it is pretty awesome. This would be their forth giveaway and it ends in May 1st:
I was a little skeptical at first, but they never ask for money (it is completely free) and they are secured by Site Lock. They also have a bunch of pictures of their previous winners on their reviews/testimonials page. So far, my experience with them is nothing but good.