I was looking around the net and found this cool item. There was a 16k MUD competition in 2000. Ckeck out some of the winners.
http://www.andreasen.org/16k.shtml
They had two categories, high-level languages, and low-level languages. Some of the work is inspired. They list 7 of the top entries in the high-level lang. category, and 11 for the low-level because they were so good. Some like Medusa by Michael Clark has a number of player and Imm commands and chat channels. All this in just 16 kilobytes of source code, awesome.
Arureal
High Lord of Lowbies.