Bing.com/rewards and then you can make up to five rewards accounts on your IP. Each day you perform searches for credits. Across 4-5 accounts it doesn't even take more than a couple minutes each if you know how to do it quickly. You then redeem credits for a variety of items (I got Amazon gift cards). Unfortunately, I doubt you'll be able to get enough credits before this sale ends.
Don't try to abuse the system with multiple IP's. They'll catch you and put down the banhammer.
So after I got an account, my brother (in the same household) made an account and started searching too and he got banned 3 days later. This was like 5 months ago though.