I went back to work today and discovered that something is preventing my computer (and mine only) from running our software in the debugger, where I watch it load a different version of ComCtl32.DLL than anyone else is using and then crash in the kernel. Oh, joy. Oh, bliss. This is what I get for loading Microsoft's beta version of their AJAX support, I suspect. Unfortunately, uninstalling their AJAX didn't make the DLL or the problem go away.
It did, however, waste an entire day at work.