Someone over on the Lego website recently built these 3d model pony lego ideas. Sadly, they aren't real, but the thought is there! These in particular are based off of the KP Shadow Squirrel's that have been floating around all over the place.
The actual mechanics seem like they would work even without legos. You guys do have some pretty wild OC ponies with mismatching parts. I should know, they all invade my inbox!
You can find the page for it here.
Now on to the discussion. What type of merch would you like to see ponies invade?