In reply to Nic:
Yep, there are some good camping spots in that broader area and you can go in nearly any direction from Nant-y-moch res to find something. The Wales Tourist Authority has used a tagline about it being 'the big country'. It's not, really, but this part of mid Wales is BIG and there are big vistas in all directions. That area between the A44 and Mach. is great.
oh - and if we're on chippies, Evans' Plaice in Rhayader is pretty excellent!
Post edited at 19:44