sharing one r/w unix filesystem between different machines and users

[Christoph Groth <cwg@falma.de>]

Hi,

I'd like to share the data saved on an external USB drive between
different (GNU/Linux) machines, each having different users.  Each user
should be able to mount the drive and read and write any files as he or
she pleases.  The users aren't necessary root themselves.

Is there a way to implement such a scheme with a non-windows filesystem
like ext3?

I understand how Unix file permissions work.  However, for a removable
drive which might be connected to different systems (with completely
unrelated uids/gids), assigning fixed uids/gids to files just doesn't
make any sense.

What's the best FS for sharing data between unrelated Linux systems?  Is
it really FAT or NTFS?

Thanks,
Christoph