I haven't ever been much interested in remailers, preferring overlay
   networks, but have been repeatedly implied to look into them by varied
   sources
   remailers have a public key, which rocks
   mail and transmission instructions are encrypted to the remailer via
   normal email
   the remailer decrypts, and sends on.
   this can let one form onions.  including with cover traffic, I imagine
   - I wonder how to find remailers
   - I wonder what codebase is presently in wide use
   - I wonder if there's a way to measure traffic
   - I wonder if a remailer codebase is portable to public logging, to
   measure cover traffic and reveal a portion of any possible compromises