Lutris is an open gaming platform and manager for Linux. It provides an unified interface for installation, configuration and foremost launching games. It works with native software, installed Windows and DOS games, Steam, Desura, online/browser games, as well as games from the over 20 supported emulators. Aquiring new games from any channel is helped by community-contributed installers. It comes prepacked for a few major distributions.
vDos is a DOSBox fork which omits some graphics and gaming emulation in favor of supporting old DOS text-mode and business applications. It adds a live filesystem bridge, file and record locking, Windows printing, scalable screen fonts, and other features. It's rather convenient to set up, runs on Linux, Mac OS X, and Windows systems.