I use Anaconda on Win7, like it a lot, but I haven't figured out how to use, say, the python 2 that comes with anaconda alongside the python 2 that comes from python.org. I've looked around, haven't really understood what I should be looking at for that. But whatever it is, it isn't virtualenv if you use Anaconda.
True, but conda has its own virtual environments that work quite nicely. You can make a new one with conda create and switch between them with activate/deactivate. You even get the same sort of interaction with pip (for the packages you want that aren't in conda or binstar), and I've been able to use e.g. Emacs packages that expect to work with virtualenv and have (mostly) had success using conda's envs instead.
How would you use conda's environments to switch between Andconda's python 2 and python.org's python 2?
"Why would you want to ..." answers are generally pretty frustrating. It's a big universe with a very large possible set of individual circumstances.
Can this be done?
I'm not sure "whatever was built" refers to in this case. Some kind of app? Of course you can use anaconda for normal library or application development, since there's functionally no difference between Continuum Analytics' python builds and the python.org python build.
C:> python -c "print 'hello'"
hello