You could brute force it by using common network names and seeing which ones get bites. Take it a step further and generate expected patterns ie. "2WIRE123". I'd expect "linksys" alone would grab a surprising amount to start, though.
Exactly, even if it's not broadcasting network names, almost every student in the Netherlands will have the train's WiFi hotspot in their list of networks.
One thing I still want to check out is whether the laptop will connect to an open network with the same name as a known network that was password protected.