Damn! Is there ever a time when you're not reading every forum?

I have several test tones and sweeps and so forth. I'm just curious if it could be done in software rather than by creating all those files and playlists. It'd be nice to have it adjustable in 1Hz increments just for the anal tweakability bragging rights of it.

To a non-programmer like me, it doesn't sound very hard in theory. In practice, how hard would it be?