Boxer for Mac allows you to play DOS games on your Mac. It uses DOSBox emulator to run games, and provides very nice looking and easy to use interface.
Installing games is as easy as dragging a zip file to Boxer. All the games I tried so far worked without problems.
One nice touch is the ability to set cover image for each game, and Boxer provides “shelf” view where all the cover images are laid out nicely on a shelf.