A year or so, several restuarants had talked about providing free WI-FI access to their customers. In fact, before it wend out of business, I used to frequent my favorite coffee shop (not Starbucks) mostly because of the free wireless. Lately, I've been going to Panera's - in the middle of the afternoon, it's usually not crowded, and their connection is pretty good. The coffees not bad, either. It seems like I'm not the only blogger there - the folks at Truck and Barter use it too.
I notice a lot of the "notebook crowd" there, typing and caffeinating away. I've talked about this in class - the WIFI requires some fixed costs, but not much in the way of marginal costs. It provides positive externalities, because it increases sales of coffee (which is pretty high margin) and other foodstuffs.