Three years ago I wrote a post about getting Dark Forces (DOS, 1995, LucasArts) running under Windows Vista. Well, I got it working under Mac OS X (I use Snow Leopard) easily.
Here are my updated directions for Mac OS X:
(1) Copy entire contents of the Dark Forces CD to a directory (ex. ~/Games/Dark). Keep the directory name to 8 letters or less.
(2) Download the latest Mac OS X version of DOSBox and install it.
(3) mount c ~/Games/Dark (or wherever you put the game on your hard drive)
(5) subst p: c:
(7) cd dark
(8) type either imuse or dark to run the sound config utility or the game
To go in/out of full-screen mode, press Option-Return. That's it - it works great!
UPDATE: I forgot to mention, for Mac users there is an awesome program named Boxer that will wrap your DOS games up in a simple app file and you just double-click to launch. It's really amazing. Check it out here.