I think gaming is by far the most common "fall-back" activity. Obviously, this is a "laptop only" scenario... I mean how practical is it to set up a desktop there for 1 to 1.5 hours?
Other things we can do there is address a particular question or concern on a particular machine. 1 to 2 hours for a single problem isn't so bad to do within those constraints.
Most of all, we can eat the health-food they serve there and just hang out.
But when it comes to gaming, I have a USB powered 10/100 ethernet switch (it has been rigged to draw power from a USB port instead of a wall outlet... very handy) to link multiple machines together. If someone has a broadband card, we can even share internet to some degree.