I like Ottawa's Charity idea. I support some local charities (where I know the people personally, and can trust them). I know some of the needs, and how the card would be put to good use, as opposed to wasted (on myself). Or they could use it in one of their silent auctions. The feel good benefits of this would be far greater than owning something not needed. I've never thought of this, but it's a wonderful idea, and I'll be adopting it myself.
Edit:
I thought I'd add that the most recent gift cards I received were Home Depot, Lowes, Amazon, and Starbucks. The first three were well needed for my home projects (got some nice under cabinet lighting parts from Amazon) and used by me. The Starbucks were given to the wife.