We have a Luggable Loo, which is basically a 5 gallon bucket with a toilet seat. It's cheap (actually cheaper than building a groover from an old 20mm ammo can) but also simple and does the job. It's not something you'd substitute for a real chemical toilet or outhouse, but also takes up less space. We use standard WAG bags available from various places, PETT, etc. The toilet and enough bags for a couple of weeks all fit inside the bucket. We don't have a privy, but borrowed Uncle Ben's for Rubithon. Normally we'll just carry the toilet out of sight, but then again we're usually not in a big group setting. For CM or the like you probably want a privacy tent.