MyPoints

MyPoints (<--- click on this link for 100 bonus points) is one of the first sites I joined back in '95.  Yes, I've been an active member for 17 years. Wow, that makes me sound old. You earn points on this site for doing lots of stuff, including:  reading emails, clicking on links, searching the web, rating websites, playing games, shopping (say, if you normally shop at Bestbuy.com or want to rent a car through Avis.com or even book a flight through United.com or use any of their other 100s of merchants, you can earn lots of points for those purchases).  They also have printable grocery coupons!
    In my 15 years, I've earned 48,635 points. The very first prize I earned was a $50 gift certificate to Tower Records (man, do I really, really feel old now).  I think I then went on to purchase my very first CD with that gift certificate (I think it was Ugly Kid Joe. I liked their "Cats in the Cradle" cover).  Given how expensive CDs were back then, I probably only had about $20 left on that thing afterwards, but it was totally worth it!!
    Since then, I've earned countless gift certificates (which means over $500 worth) to Amazon.com, iTunes and other merchants I am too drunk to remember right now. Either way, click on my link to MyPoints. It's worth your time.