Limit 3 per customer
Practically everyone eventually spends $50 in the iTunes Store, whether on apps for an iDevice, MP3s to play at home or on the go, or updates for OS X. Given this, today's deal spotted at Staples is almost like free money. $50 iTunes card for $40
You'll need to pay $1.99 shipping to give post office tracking capability, but otherwise this deal is about as good as it gets for iTunes money.