That's right, it's entirely possible to build an ArtNet node from the above. At first I was a bit wary that the router's CPU wouldn't handle it, but after testing it seems to be working fine.
This came about after I wrote libartnet. I started thinking it would be cool to have Linux running on an embedded system that could act as an ArtNet node. The only embedded system I'd used before was the Linksys WRT54G routers but they don't have USB ports. After looking around a bit I found the Asus WL-500 and the Netgear WGT634U which supported USB devices. I choose the Netgear as it had more flash and RAM than the Asus, and I could get hold of them easily through a wholesaler.
A couple of sleepless nights, one bricked router and a lot of experimenting and here is it...
These are approximate, your costs may vary:
Known to work: DLink DWL-520, Dell TrueMobile 1300 (Broadcom BCM94306)
Problems reported: DLink DWL-G510
Known to work: SVEC FD1811, Linksys WRT54GS
The ultimate aim of this project would be to have a buildroot so that users can download, build and install the image in a couple of simple steps. At the moment I'm miles away from having that ready, so your best bet is to follow the steps here. (But be warned, much of the process is still undocumented.)
The router comes with 5 ethernet ports as well, so not only can it drive DMX lights, but it can act as a distribution point for more ArtNet nodes.
A big thankyou to Jolt who modified the 2.6 kernel to run on the router (and who answered all my stupid questions :).