Circuit City

Full review
I ordered an ipod nano on circuitcity.com and opted to pick up my purchase in the store. I get better rewards on my credit card if I shop through their online partners, so to save a few more dollars ($8 to be exact) I chose this service. I've found that circuit city usually has the best prices around and a lot of times they offer incentive deals (my dad just bought a digital slr camera and got a printer, software and accessories for free).
The online checkout is very easy to use. It was easy and convenient to select the store that I would pick my purchase up at.
However, you do have to print your receipt off and show up at the store with this and your ID and the credit card you used for the purchase. Some people may be in a hurry and miss this. Once I got to the store, there was a spot clearly marked for me to go and pick up my ipod. They had it ready and verified my documents in about 3 minutes. While this option was convenient and profitable for me, unless you're in the same situation, I would recommend just going to the store and buying the item or having it shipped to you because I don't really think this option saves a lot of time.