A while back I posted about some Horse Mount Miniatures from StufferShack.com. It's a great idea: these horse miniatures are offset on their base, giving you room to set your rider mini on the same base. But why stop at mundane horses? More recently they've added some Exotic Mounts. Your minis can now ride panthers, drakes, unicorns, griffons, and more. So far I've only ordered one of them, the Tourqen Panther. I plan to order a few more of them when I have some extra money. These cost a little bit more that the horses, but they probably use harder-to-find minis. They do have a buy-4-get-1-free deal, so you can save a little money there.
Here's some pics of my panther (click to view larger):