Attaching a 14foot trampoline to a homemade raft.?

Okay, so last fall I brought a trampoline for a steal, and I can get plastic rain barrels cheep too. I am a smart guy, and I know this is absolutely possible, but what I want to know is how dangerous do you think it is? And are there laws agents a contraption like this? I've been all over the Internet today and can't find one person that has ever done this. Would I be the first? I find it really hard to beleave this hasn't been tried before. Seeing as a 14 foot water trampoline costs like two grand and this could be put together for prob. Less than $200.