Hi - For what it's worth, I set up the Hanover High School (Hanover, NH) network a few 
years ago with about 28 AirPort Extremes - the last version shaped like a spaceship - and 
I think it's working fairly well, so here's what I did. I set up a VLAN (subnet) for the 
wireless traffic. Roaming won't work so well across multiple subnets. The other trick was 
that we found that firmware version 5.7 wasn't as good as 5.5.1 - the APs would go 
"deaf" after a while. So we used the program "AirPort Extreme Firmware 5.5.1 Updater" 
(from Apple's site) to downgrade all the APs to 5.5.1. We bought the Power over Ethernet 
versions and used "AirPort Management Utility" to set them up. I set up the radio 
channels for each AP, laying out use of channels 1, 6, and 11 to minimize interference 
between APs. 

Yes the AirPorts aren't really enterprise class APs. I keep watching for some vendor to 
come out with enterprise class wireless that schools can afford. If you have a lot of 
money, folks like Aruba and HP and others have sophisticated solutions. I'm still watching 
for inexpensive APs with multiple SSIDs and POE and nice management and reliability and 
dual radios, ... 

Now I'm at a different school and I'm using the Linksys WAP54G that others have 
mentioned as a cheap solution and it has worked fairly well, although some of those APs 
have to be unplugged and restarted once in a while (which would be unreasonable for 
permanent installation in ceilings, etc!). I tried Linksys's "business" model (WAP54GP?) 
but it has some oddity with WEP that Linksys never fixed so that it doesn't work like the 
WAP54G; Macs and Windows computers can't share the same SSID and WEP settings. 
Linksys acknowledged the problem but that unit has never gotten a firmware upgrade. 
This summer I will see if the WAP54GP works better with a better security setup. 

The first requirement for reliable wireless is to have a reliable, managed wired 
infrastructure. If you're using a network built on consumer desktop switches I'd start by 
upgrading that before trying to put a wireless network on top of it. 

Steve Ligett
Crossroads Academy
95 Dartmouth College Highway
Lyme, NH 03768