Here's our site
http://opendevicelab.com/ which is at the moment missing lots of content (most of the links just go to my own site).
We decided to take a bit different angle when we started up the device lab. Instead of worrying about schedules, insurances and the amount of devices we have, we just basically put up a site and brought our devices to the office and announced that anybody is welcome to visit the lab and use the devices. That’s basically what Clearleft and the London lab did too. After three or four weeks our device number has already doubled (donations and loaned devices) and we now have 29 test devices.
I know that it's possible that the lab will get popular and have lots of visitors and that someone might be using the devices when someone else comes in, but only time will tell. If that happens and if we feel it starts to become a problem, we'll think of a better plan. But not before.
About the charging: We are charging almost all the devices through powered USB-hubs. Jeremy Keith also told me that they have all the devices running through a wall socket that’s on a timer which switches the power off in the evening and night time and back on again in the morning. That might be useful for saving some energy and also to keep the batteries healthy.
We don't really let people to take the devices with them, but they can bring their own laptop and spend time at our lab while testing/working.
As I said to Jason on Twitter earlier, I've been writing an article about how to build a device lab, and it should be live on Smashing Mag soonish, probably sometime during the next week. That will explain a bit more what's happening with our lab and how we got things up and running.