I just found out about
Code::Blocks, an open-source IDE. If you look at their FAQ, you'll see that one of the compilers you can use with this IDE is *drumroll* Visual C++! Apparently Microsoft has been giving away their C++ compiler as a free download. Between that and this IDE, you've essentially got their $100 plus software for free, legally.
ADDITION: Hookay, I just noticed
this at Microsoft's site. Am I missing something here, or are they totally just giving Visual Studio away for free? Note that the Toolkit is a 30MB download, while this is only 3.