I like JMK’s “Neep” fonts, but they are not readily available for Mac OS X. I have converted NeepAlt to dfont and made it available here. The results are a bit wonky in that I think they only really work properly at 15 points size.
All credit goes to Jim Noble. (Unless the fonts look really ugly on your system, and then that’s probably my fault and not Jim’s.)
See downloads in this section.