If you're in the market for a new Samsung Galaxy S5, you might want to take a look at Best Buy. They're offering a $50 Best Buy email gift card with the online purchase of a new Samsung Galaxy S5 on contract from their online store. If you buy the phone online and off contract, Best Buy will just throw in the gift card with the purchase and ship it to you with the phone. There's probably some sort of agreement with the carriers and/or Samsung that they can't offer the gift card directly with the phone.
If that's not good enough for you, you can take your old phone in to a Best Buy store to buy a Galaxy S5 in person and get a minimum of $100 for the trade-in. Best Buy can and will offer more depending on the phone, but at the bare minimum you can walk out of there with a $100 gift card in your pocket
Alas, you can't apply any of those gift cards to the purchase of the Galaxy S5 itself, so you'll still be looking at $149.99-$199.99 depending on the carrier out the door for a Galaxy S5 on contract, and $649.99 off contract.
That said, does this offer tempt anybody?
Source: Best Buy