Here’s another article from Game Creation Society, where we use several different programming technologies to develop semester-long projects. This is mostly geared for students who already know programming, but want to find out more about game-specific platforms. Even if you’re not a student or programmer, however, this list should serve as a good place to start. The list is biased toward technologies that I’ve already worked with, so I’ll add more as I get more experience!
Flash/Actionscript

Flash is the go-to technology for making 2D web games, and it can be very powerful if you know how to use it. In order to collaborately make Flash games, you’ll need to program in ActionScript code, instead of the Flash CS-whatever environment. Adobe also has decided that giving software to students for free is cool too, so you can actually register for a license for Flash Builder here: http://www.adobe.com/devnet-archive/flex/free/. It takes about two weeks to process your license, so in the meantime, you can download a trial here: https://www.adobe.com/cfusion/tdrc/index.cfm?product=flash_builder.
If you’re planning to make a platformer or a top-down game in ActionScript – especially if you’re short on time or programmers – I highly recommend using either Flixel or FlashPunk. They are ActionScript libraries used for making Flash games with bitmap graphics, and they’re typically used for indie or retro games. Flixel has more documentation and community, but there’s a bit of fragmentation due to different versions, so take a look at some tutorials and samples to decide which one you prefer.http://www.flashgamedojo.com/ has a good collection of tutorials on both libraries to get you started, and there are additional tutorials on their own websites (http://wiki.github.com/AdamAtomic/flixel/ andhttp://flashpunk.net/?p=tutorials).
These are some fairly verbose guides to ActionScript 3.0, so if you’re not feeling very uncomfortable with the language, these are great references: http://www.adobe.com/devnet/actionscript/as3.html,http://help.adobe.com/en_US/AS3LCR/Flash_10.0/index.html, and http://help.adobe.com/en_US/ActionScript/3.0_ProgrammingAS3/.
Visual Studio/XNA

If you’re developing in C# or C++ on Windows, you’ll probably want to use Visual Studio as an IDE. Luckily, if you’re a student, you can go to http://www.dreamspark.com to download Visual Studio 2008/2010 Professional for free! This gets you an academic license that will last you throughout college, but if you’re working on a commercial project, you can always just download the express versions from here: http://www.microsoft.com/express/Downloads/. Read more