What sort of giraffe do you have? Can you freemount it? Are you good at dismounting safely?
Giraffe MUni has been done, but I don't think it's a very good idea, especially not if you mean hardcore MUni. Light trail riding on a giraffe shouldn't be that dangerous, and would definitely be do-able.
I suggest you learn to freemount before you look at MUni or other activities on your giraffe. You don't want to be stuck on the ground a long ways from a pole or wall or ladder or whatever you use to get on. Freemounting a giraffe is not easy, but it's not terribly hard either. I suggest you spend some time working on freemounting, because it really does make giraffe riding a whole lot more enjoyable.
If you want to do MUni on your giraffe, you should probably also learn to dismount without letting the unicycle roll. The way I do this is to pull the seat out in front and immediately jump off the pedals, while still keeping hold of the unicycle. The advantage of this method is that the unicycle stays vertical; it won't ram into rocks or trees with potentially dangerous consequences.
A little late on the draw. Anyway I have been wondering. What kind of a frame would be appropriate for GMuni? I would think most frames would get wrecked by this. I don't have a giraffe, but I have just always wondered about this.
My giraffe hasn't gotten at all boring in the five months I've had it. There's a lot of fun freestyle tricks you can do on a giraffe, plus some cool mounts like the rolling mount and the frog mount. I can see how it would get boring if you don't like freestyle.
You made a thread a while back asking about riders from Spokane. I replied to it, but you must not have noticed. Anyway, I usually ride in a park in Liberty Lake, but if there's snow, sometimes I'll ride at the skatepark downtown under the freeway. Because of college, work, and snow, I haven't been riding much lately, but it would be nice to go for a ride sometime, maybe when we get better weather.