Hmmm - 'Money Tree' is used for various plants for some reason, but if you do have a crassula (Jade) tree, yes they're used a fair amount. They're not traditional bonsai, not having the type of growth pattern or early woodiness that other trees do, but if you use some imagination and know how to grow the plant, then feel free to go ahead. Wire is not generally used on them though, because it could damage them, however gentle weights are used to slowly pull down branches sometimes, and you can of course twist off the leaves and they'll grow back double, or you can cut branches to change the shape, plus they respond very well to sunlight, and will move toward it (to develop one side, for instance).