Hmmm, interesting. According to Alan Reiter'sweblog which he's been updating from the Technologic Partners Conference, Mesh Networks is beta testing a low-cost repeater-router for extending the range of 802.11. Basically, the MeshNetworks software creates a, well, mesh network, for your existing WiFi system.
Hmmm, I wonder if this is possible without breaking the 802.11 standard - In other words, I can see you turning a PC into a black-box repeater, but I don't see how they could turn it into a repeater AND still allow you to use the box as a wireless node on the network. Perhaps I'm missing something, or perhaps we will all need to download some client software (that'll be windoze only, of course). Still, it is an intriguing idea - they are looking at an embedded product with MSRP of $60.
Actually, as I read Reiter's post more carefully (pardon me, I still haven't had my morning coffee), it looks like Mesh Networks is trying to do something like what we've done - turn a PC with broadband connectivity and a WiFi card into a Mesh Networks AP. Well, if that's the case, just go and download our code, it's free and available today...
Something to keep an eye on.