Dear Lazyweb/Geeky Question

Just out of curiosity,

I'm looking for a low cost, small, quiet box, likely to install linux on to be a network server.
Mostly, it's to share a large external hard drive, and possibly to host a DLNA media server (for the PS3).

So, basically the requirements are:
Cheap
Small
Quiet
USB 2 ports
Can run Linux (with samba, and a DLNA/uPnP server... or otherwise can do this without linux. It would be nice to have a linux server around though.)

In an idea world something like the Mac Mini would work great for this, but it's not *cheap*. A 40 GB PS3 would also work, but it's not particularly *small* (and maybe still not *cheap*).

Any great and wonderful solutions would be appreciated.

I'm currently using an old laptop for this (meeting everything but USB2 ports, the external hard drive is slow! tee hee!)