Assuming you shop at Raley's/Bel Air enough you can increase your stimulus checks by 10%.

Raley’s, Bel Air and Nob Hill Foods customers who bring their economic stimulus checks in will be able to add additional dollars to their food budgets. Each of the company’s 125 stores will convert stimulus checks to gift cards and add 10% more, giving customers more dollars for household spending.

The service runs May 9 through July 31, and will allow shoppers who bring in stimulus checks in amounts up to $1,800 to convert those checks to gift cards and gain the 10% bonus, without a service fee. For example, a Stimulus Check in the amount of $300 would be converted to a Raley's gift card in the amount of $330. The gift cards do not have an expiration date.

http://www.raleys.com/features/001.jsp?featureid=843203

I think Home Depot is doing the 10% thing too! I'd probably get the most bang for my buck there. Of course, food is probably the most practical way to go, other than paying down debt.