Many of the hype-fuelled municipal WiFi plans made by various cities across the country involved free services supported by advertising. The party line was that businesses would love the chance to advertise to users in their immediate vicinity, while users would eat up the free services. Unsurprisingly, like muni WiFi in general, the actual deployments attempts at generating ad revenues have failed to live up to the inflated expectations. One of the biggest problems was that advertisers would have to do deals with individual networks, making it much more difficult to get make a wide ad buy than with other media like traditional web ads. That's starting to change, as a handful of companies are sprouting up to set up nationwide ad networks, allowing marketers to make purchases across multiple muni WiFi networks. That's a good step, but it's not a complete solution. Many networks have had teething problems that that have generated bad press and hardly encouraged usage, while the idea that businesses will pay a premium to advertise to local users may be oft-repeated, but remains unproven. One area where WiFi networks are seeing strong ad sales? Airports and hotels, where the attraction for marketers is a high number of business travelers. The different demographics of free municipal networks may not dictate the same level of demand.