A while back a group calling themselves Overmare Studios were working on a Fallout 3 mod with ponies, but eventually decided to move to the Unity3D engine and release a standalone game based off of the influential fanfiction Fallout: Equestria. Months of painstaking development lead to this video, showcasing the incredible, never-before-seen ability of picking objects without resorting to hands or magnetic hooves: magic (i.e. how Gordon Freeman picks up the can before he is given the Gravity Gun). Hopefully this will lead to HL2-like shenanigans such as tossing kitchen sinks at hostile wasteland inhabitants, but even if it doesn't there should still be plenty of fun to be had...hopefully.
It's more than a bit early to form a real opinion on the game, although I do have doubts about the team's ability to create enough textures, given the probable size of the game.
Obligatory pony.