A possible solution is to run
VNC (NOT VLC media player) server on your computer that will be serving "streams", and network that along with the P3s and run the VNC client on the old P3s and you can even run a lite client off your USB key at work.
Check the link for VNC software you could use.
Best solution? No
Is it versatile? Yes
Is it easy? Pretty much, requires no haxx0ring.