The Samsung Galaxy S6 Edge isn't different from the regular S6 on the inside, but the outside is another story. The phone tapers down on both sides to form something that's arguably prettier and harder to hold. Either way, it comes at a higher cost. T-Mobile sells the phone for $780. AT&T wants $815.
Fortunately, you can currently snag one on eBay for $670. That undercuts T-Mobile's price by $110.
The units on sale come with 32GB of storage. They're unlocked, and folks in the States can use them on either AT&T or T-Mobile. Colors offered include black, white, and green. Gold is out of stock.
Shipping is free. The seller is willing to mail units out to much of the world, though most of Africa and Latin America is noticeably absent. Other exceptions include China, India, and Japan. Alaska and Hawaii are out of luck as well. The list is all over the place, so be sure to scroll down to the shipping and payments section of the link below.