[Dylan16807]

I don't have an easy way to try a test corpus but I fed this comment page into it.

  Raw size:     37409
  gzip(raw):    6170
  gzip(base16): 7482
  gzip(base64): 10675
  gzip(base85): 10549

So it works better than base64, and it has the advantage of working 4 bytes at a time rather than 3.

Also note that when you're feeding in binary data the gzip sizes for raw and base-xx data get a lot closer together.