Ally Bank has been listing weekly cash back offers of its Ally Perks program. The latest deals (valid until 11/1/2012) are shown in this Ally Bank blog post.
The best one in my opinion is $5 back on $50 purchase (in-store or online) at Lowe's. To qualify, you just have to make the purchase with your Ally checking debit card.
It's a small bonus, but if your purchase is $50, it's 10% cash back. It's easy money if you had been planning a Lowe's purchase.
I reviewed Ally Perks