A new game added to GOG.com a few days ago called "Mainlining", and it apparently has some pony under the hood. The point and click hacking style adventure has the website above as one of the places to visit, completely with a pretty obvious FiM pony and fanfic. This was actually found in the trailer, so I'm not too sure how extensive the cartoon horse is within it.
If you are curious, you can find the trailer below.
Thanks to Anonymous for the heads up.