WOW. My head just exploded. If there is any really unique game around, with real educational and scientific value beneath the surface, that game is Creatures. At first sight, this game might look as some Tamagotchi Plus, or a "cute alien" edition of The Sims. However, it's much, much more than that. Want examples to back that statement? Here's a link describing the AI used in the Creatures series: http://aigamedev.com/open/highlights/creatures-ai/ And another article describing its take on biochemistry: http://www.gamewaredevelopment.co.uk/creatures_more.php?id=460_0_6_0_M27 Yes, that's right - it simulates DNA and genetics, including mutation and evolution; it simulates biochemistry in a variety of levels; it simulates brains with several "lobes" containing adaptive neural nets. And what do you have with all that? Emergent behavior all around. Your Norns really "feel" alive. And they pretty much are alive, within the constraints of a computer simulation wrapped in a game. If you look beyond the (brilliant) Artificial Life simulation aspect, you also have a variety of environments in which your creatures can live (and die), all sorts of machines and gadgets (that you can connect in order to make them work together, with the possibility of emergent behavior as well), and lots of things to do. Creatures can be a game, or a lab, or both, depending on how you look into it. Still, it's probably the most unique game ever created, still unmatched in its ability to succeed in providing a realistic simulation of life - with all its ups and downs. It can be a powerful learning tool, a great game, a brilliant experiment - and, in the end, it's truly a masterpiece, in more ways than one.
IL-2 is a fantastic flight simulator. While many flight simulators have their strengths and weaknesses, the IL-2 series became the pinnacle of the WW2 era flight simulator genre - it has everything: a fantastic flight model, great damage modelling, many (well-modelled) aircraft to fly, and good artificial intelligence, along with great graphics and sound. It's also very approachable on the difficulty level, due to a wide range of settings, to accomodate both the newbies and the hardcore flight sim fans. No other simulator comes close these days, when you consider all those parts; IL-2 is the ultimate package for any flight simulator fan. For those who like single-player, there's plenty of options. There are pre-made missions, an assortment of (dynamic!) campaigns, and both a quick mission editor (for practing dogfights, for example) and a built-in mission editor which is very capable. The dynamic campaign engine is great, but make sure you update it with the latest version (look for further information on the game forum, I'll see if I put it there). If for some reason you don't like the missions generated by the built-in dynamic campaign engine, there are a few free third-party options available as well. It really, really shines in multiplayer. You can fly missions competitively or cooperatively, in many different maps (in missions made with the mission editor, or even dynamic campaigns), and it works beautifully, even with some moderate lag - I could play well in some servers even with a 400-500ms ping. I've played this game in multiplayer more than any other game I own (and on a 56k modem at the time), and it has always been a blast, a real exhilarating experience. All in all, this is one of the gems of the combat flight simulator genre. If you like flight sims, you probably have this game already. If you don't have it already, get it now. It doesn't get much better than this.