If you weren't aware of Massdrop, they're basically a group buy company. You sign up for a drop, and so long as enough people are on the drop, the group gets the product at the group pricing. It's basically a means of getting a bulk discount. They've also worked directly with manufacturers to develop products, and most of those are sold traditionally (without the group buy).
Anyway, they've got a couple of good ones worth mentioning, especially if you like good sounding headphones. The AKG K7XX is the most comfortable pair of headphones I've ever owned, and the red edition is going for $160. If in-ears are more your style, the NuForce EDC3 is down to $75. (I haven't tried that exact model, but the HEM1 has been great.)
They've also got some neat Sci-Fi Patent Prints, and a ton of other assorted products.