We're about to find out.
Netgear, a reputable name in routers, has launched the WGR614L, an open source 802.11g router.
It looks like any other Netgear router, it can even run under Vista (thanks Nachi), but it can run everything at a new Netgear site, MyOpenRouter, and more besides.
While Cisco accidentally created an open source router a few years ago, getting caught with Linux in its Linksys, the company never exploited this as a feature, but treated it as a bug, blaming chip supplier Broadcom.
Netgear is definitely treating this as a feature.
MyOpenRouter offers developers a comprehensive user guide, applications forums and downloads. Best of all this isn't a stinky would-not-sell-otherwise router. It's got an internal diversity antenna to improve performance, and supports WPS.
Nachiketa Prachanda, no relation (we assume) to the Nachi worm of five years ago, seems to be the main host-blogger at MyOpenRouter, and that's a great idea because it immediately personalizes a site, gives it a voice.
So if there is a substantial open source router market out there, in 2008, Netgear will find it. I just wish the industry had this attitude back in 2003.