Bone to be wild!
They're not as expensive as other things like boxing bags, bench presses, etc. and they leave you with a buttload of upperbody and core exercises. But yeah, they're still not exactly cheap.
I'm pretty bad at sticking to routines, I'm lazy and horribly uncommitted. I do have a few exercises that I tend to focus on whenever I choose to play on the rings. Yeah, play, not workout. Playing is fun and I have fun. I tend to do dips, L-sits, tucked front levers, ring swings (holding myself up, with my palms facing forward and swing), just holding myself up is hard enough as well and the odd set of pullups. I really need to do more pullups.