Can You Make a Steam Library Accessible to both Windows AND Linux?

Is it possible to have a Steam Library folder that I could put on a HDD that could be accessible from Steam in Windows AND in Linux? Or is the code different enough I would need two installations of the games I wanted to access from both?

Making the hard drive accessible is trivial. The executable files are completely incompatible, though. I'm not sure how Steam handles an install with both operating systems. It would be easy for the developer to read the game data from either executable, but they may require you to have two copies of the game downloaded.

The games are packed differently for every platform, so you can't share any data... a pain because I have a lot of Windows and Linux games eating space.

Some games use the exact same save data so you can symlink that together.