The credit card companies spot "rate tarts" eventually
Not really - they haven't spotted me, and i've been juggling 0% money for getting on for three years now. Rather boringly i've used the money to offset my mortgage (and can give it back if they ever ask for it) rather than blowing it all on a Stampe, but it still looks like debt. Saved me a hell of a lot of interest though...
edit: I agree with FNG about not borrowing to fund a hobby, but if you are thinking of loans Capital One do a 3.9% "for life" credit card. With care it can be used as a very cheap, very flexible personal loan. Without care it can cost you loads though, so caveat emptor.