Supernova
I wanted to point that Supernova, a game originally written in the 1980s and distributed as a proprietary game until it was later GPLed when the company threw the code over the wall to forget about, can now be compiled and run on modern systems. In the mood for some retro gaming nostalgia? Head on over to https://gitorious.org/jxself/supernova/ for some free software gaming goodness, but pay attention to the known limitations in the Build file.
Other work includes another old game, Beyond The Titanic: https://gitorious.org/jxself/beyond-the-titanic/
I'm also wondering what to work on next.
You could try Paku Paku:
http://web.archive.org/web/20141105003133/http://www.deathshadow.com/pakuPaku
The code is in the public domain, but it's compiled with a proprietary Pascal compiler (Turbo Pascal). I don't know whether it can be easily converted to modern systems, though.
Screenshots of the games would be nice. Those could also be added to https://en.wikipedia.org/wiki/List_of_minor_Apogee_Software_video_games