Automatically demounting removeable media?

[Jim Cheetham]

I like to have my removeable media (CDs, USB drives etc) automatically 
mount when I pop them into the machine ... which Ubuntu achieves well.

However, I also like to have them un-mount automatically, after a few 
minutes, so I can just grab them and walk away from the machine ...

The corollary to that is that the devices should re-mount when I try to 
access them ...

autofs achieves this well, for my USB drive at least, but interacts 
badly with whatever is mounting on /media for my CD drives ...

Can I achieve the same result with the default mounter, or can I disable 
the normal mounter and use autofs instead (maintaining the nice 
integration with Nautilus?)

-jim