They also use the commotion (https://commotionwireless.net/), an open source software project that runs on commercially available wifi access points and routers and creates the mesh network.
Case study: http://www.scribd.com/doc/147627564/Red-Hook-Initiative-Tide...
+ Ubiquiti (founded by Robert J. Pera, hn might appreciate his entrepreneurial background, look him up) + Artemis (founded by Steve Perlman, another hacker/entrepreneur ) + Meraki (aquired by Cisco in late 2012, seems like this one did actual mesh networking in MIT and SF)
It seems like there is a lot of noise around these wireless technologies, what is holding back adoption?
Community networking over community networks could be a thing, but bootstrapping is hard, and it can be hard to see the point. "Buy this thing and set it up and you can talk to people within shouting distance with your pc/phone" isn't super exciting.
Maybe the problem is they're doing it from the wrong angle. Don't create a mesh network independent of the internet, create a mesh network integrated with the internet. Then use whichever interface has the best performing route and use them to back each other. So if your wireless goes down you can still use Comcast and if your Comcast goes down then you can seamlessly use your neighbor's Verizon.
Existing 802.11 ad-hoc is half duplex & CSMA, if you build a multihop mesh with that on omnidirectional nodes you get greatly diminished performance across the network. TDMA is not really better, the whole thing degenerates into a distributed graph coloring problem. You can have a lot of success building a network of point-to-point links but again you only really see people getting excited because they need non-wired infrastructure or because they like the technology. The Ubiquiti gear is really good for this.
Meanwhile you might wonder about doing this on small battery powered devices. It's very difficult to build a mostly-asleep power management scheme if a device needs to be awake to relay packets.
I still think there's promise in the area though and do follow what other people are doing.
I set up a point-to-point link a few weeks ago using two of their cheaper antennas - it took minutes to configure the encrypted, secure connection - it "just works".
I'd love to join a mesh network (or a p2p node network) where I live, but there doesn't seem to be one available.
In Melbourne, Australia there's a rather large wireless network that's existed for years - but I can't find similar networks in any other of the country's large (or even smaller) cities.
Contact details are in my profile.
I really enjoyed this HOPE X talk on this subject: https://www.youtube.com/watch?v=cEo4uLAJ32U