I have nice (and very welcome) guests in my Minecraft world now.

Mod: Animal Bikes 1.4.7
Building a pony bike lets you enjoy 54 different ponies as useable mounts. Surround a saddle with 8 diamonds to have access to your ponies. The spawned pony is random and the item depletes over time.

Edit: Right clicking the spawned pony will make it disappear again and refill a part of the item durability.

I just thought I'd share this here for those who like minecraft but didn't know about this mod.

Link to the download:
http://www.minecraftforum.net/topic/762794-147-animal-bikes-splanmp-added-batchocobo-and-silverfish-bike/