Physics 101 SE
The perfect solution for physics students and teachers everywhere, Physics 101 SE is the premier physics calculation tool, allowing you to focus on physics and not mathematical busywork by working...
http://praetersoftware.com/download/demos/DEMOphysics101windows.zip - 6Mb - Download - Screenshot

Babala
Babala is a fun and fanciful game suitable for all ages. You fend off the enemy muggers (they can't shoot) on a basic grid, amid obstacles and booby traps. The game's defining features are mercifully simple but don't be fooled, because it gets tough as nails to beat as the levels progress. ... Your shots are either projectile or mine, assuming you're so armed. ... In-game help is in English, Czech or German, as specified during installation. ... And there seems always a way to best an earlier score when you ambitiously replay a level.
http://download.babala.org/v0.3.0/BabalaInstall_0_3_0.exe - 472Kb - Download - Screenshot

Nebula Wars
Includes a vector graphics ship editor, online leader list, custom sounds, and an acid trip graphics engine! Customize everything about your ship from mass to rate of fire. Use physics to create powerful ships. Massive ships take more hits, less massive ones take less engine power. ... Big projecties connect easily but small projectiles have more pressure ripping through baddies with less velocity! ... It's up to you to figure out what combination works to get you to the top of the online charts!
http://www.mousetraparcade.com/InstallNebulaWars.exe - 12Mb - Download - Screenshot

Zirconia 2: Battle
Zirconia 2: Battle is a unique 2D "space" shooter not set entirely in space. In this game, you and a computer-controlled opponent are playing vertical scrolling shooters, split-screen style. You must defeat 7 different opponents indirectly by using cards that you will draw throughout the course... 5 cards will then added to your deck automatically, and you can choose 5 more cards from a reward card pool. ... When you defeat an opponent, you will receive upgrade points for permanently improving the stats of your choice.
http://www.z2games.com/zirc2battleInstaller.exe - 16Mb - Download - Screenshot