The development of media servers is growing apace. Just bought (£2.99) PlugPlayer for my ipod touch from the itunes app store.
I already had Null River and Twonky Media Servers which we used to stream movies to the Sony Playstation.
My ipod touch now picks up and plays not only all my FLAC files (in a seperate file on external hard drive), and the apple lossless files which I usually play through itunes.
I have to say the flac files sound much more 'analogue' than the Apple files I normally transfer onto the ipod, more sort of natural.
On top of all that. I've just discovered that all my movie files now play on the ipod as well...all accessed via Twonky Media - which cost a few bob, but now worth it. Lord...I've got 3 series of The Wire to get through.