Groupon, 50% Off One Purchase (YMMV, Ends 3/13)
Groupon is offering some users a discount of 50% for Local deals. This discount is probably targeted, but you can quickly check if you are eligible by using code FIFTY at check out.
The code is valid for a maximum of 1 order per customer. Savings limited to $25 per order. Ends 3/13.
Additionally, you can also go through shopping portals to earn more cashback. TopCashback is offering 8%.