A reminder, you do not need to enter any colleges for this challenge.
The first three are the key to understanding the fourth.
Note: The third may break in IE.
Go there. Get connected.
Ben Webb (bjw45)
This puzzle features webcams* from three different colleges. Since we don't need to enter them, maybe we should look outside them. In fact, there are three stickers on lamposts and traffic light poles, next to the entrances of these colleges that have some random letters on.
The third image is not a webcam, but rather simply a photo of a weirdly specific location. We find there is a wifi access point, and that the letters are the encryption key. Accessing the admin page of the router brings up a webpage containing the solution.
* Time being what it is, these have since succumbed to linkrot. Of course, the puzzle itself relies on an access point that has longer since been deactivated...