Before this thread gets too old, I think I should update my findings with the powerline networking. I ran into a snag that I hadn't noticed at first. This snag existed with my Orinoco Ethernet Converter as well. Basically, plugging a hub into the powerline ethernet bridge doesn't allow you to reliably access all devices on the hub. I contemplated installing a router, but I ultimately decided against it.

Instead, I installed a 802.11a access point. Here's a nifty diagram of my network that I made in MS Paint:



The 802.11a is great! It feels like I'm wired to the network. Transferring MP3s over it seems 3-4 times as fast as the powerline. 802.11a versus 802.11b is night and day. It's simply killer.