GLterm is a replacement for the Terminal application which ships with MacOS X. It's made to be faster, and to support more common terminal features. It supports full ANSI colors, all vt102 protocol, all DEC function keys, and a selection of useful xterm sequences.
The Big Thing is that GLterm uses X11 .bdf fonts and renders them using..OpenGL. So it's very fast... as long as you have a working 3D accelerator. It should work as intended on B&W G3 and up for desktops and on White iBook and up for laptops: ie a machine whose 3D accelerator is handled properly in OSX. To this date (April 2002) Rage II, II, Pro are not accelerated.