I know I've posted before about how I use swagbucks to earn some extra spending money (both through paypal cash and Amazon giftcards).
I've been using swagbucks for about 2 years and have earned $75 in paypal cash & $90 in Amazon gift cards. This might seem like not very much, but I don't spend a ton of time on the site. I check in daily and do a few of the quick daily polls and occasionally the surverys. So maybe 5 minutes a day?
If you want to sign up and haven't already, you are in luck because you get 70 bonus swagbucks when you sign up and use the special code: theurbanfam (through March 7) plus you get 30 after you finish your profile.
Once you earn 450 swagbucks you can get a $5 Amazon gift card (a $25 paypal is 2,500). Gift cards aren't the only thing you can get though. They have music, books, downloads, household stuff and more.