

FTL combines the best of Star Trek with a very roguelike feeling. It makes for a game which is both extremely hectic and highly tactical. If you either enjoy the general idea of being a captain on a small spaceship and rerouting energy and commanding members of the crew, then you want FTL. Especially at this price, the game is very much worth it. That having been said... I can't really advise you to buy it from gog.com right now, much as I love these people. Lacking the Mac and Linux versions, it'd be better to support the game via the developer's homepage or at least Steam (Steamplay support). If gog starts offering the other platforms (since they're included on the official page anyhow), then ignore this part ofc.
There's really little you can criticize about Nexus TJI. The voice acting is off at times, some of the missions have a minute or so of excessive downtime while flying, and the middle part of the story can be confusing. Beyond that, you get a game which gives you very deep tactical control in a well-done and well-presented (even by modern standards, you can change registry-values to get 1920x1080 for example) space environment, with a very engaging story and a really awesome main character (not Cromwell!). I loved this game back when it came out, and I'm still loving it now. I only hope the successor will be similar.

These games surprised me because I had never heard of them by the time the fourth came out. They're stunning. Each one is short, but the writing is really well done, the characters are great, and the production quality is very high for indie games. If you enjoy point&click at all, don't miss them.