The MudOS mudlib comes with player races but they do very little. They are
mostly there so that you have a foundation that you can build on more than
because we had any uses in mind.
  The one thing that they DO do is affect player statistics. Statistics are
rolled up between 9 and 21, and all races except human have their statistics
modified by up to 3 points either way. All modifications are zero sum, so that
the total of stats is unaffected. Thus, the final range of possible statistics
is from 6 to 24. The statistics rolls and modifications take place in the file
adm/obj/login/cretion.c, if you want to modify them.
  There are a lot of things you can do with races that are only being done
on a few MUDs. Perhaps the most common is languages: allow players of the
same race to send messages that aren't understood by members of other races.
Then you can allow dwarves to learn the elven tongue...
  Another thing you can do is make areas of the MUD off-limits to some races,
ie have a dwarf cave city where elves and orcs are not permitted to enter. You
can also make the interactions of NPCs and players be race-dependent: for
example, have a wandering monster that only attacks orcs. You can make the
player's starting location depend on his race, so that you appear in the city
of your race.
   There are lots more creative ways to use the race property and we encourage
you to go nuts with it. Having meaningful races is one way to add a lot to
the role-playing aspect of the game, to steer away from the hack-and-slash
mentality that LPs are infamous for. If you think of something clever to do
with races, send mail back to TMI and let us know what it is!