I discovered Hotspotr at SF Beta this past week. It's a neat little service that mashes up Google maps with a local Wi-Fi hotspot finder. The real pull of the service is you can rate and comment on hotspots as you would with restaurant reviews on a review site like Yelp. It's the perfect service for the casual Wi-Fi traveler to benefit from road warriors who are willing to take the time to review a wireless access point.
The ratings aren't just things such as the overall quality of the wireless signal either; you also can rate food and drink, outlet availability, and whether it's better for work or play.
One of the neatest parts of using Hotspotr is its zoom technology called GZoom. GZoom lets you draw a simple rectangle to zoom into precisely the part of the map you want. Sure you can accomplish something similar by simply double clicking on the spot you're looking for, but GZoom lets you select certain regions with much more accuracy.
Hotspotr has listings for more than 1,200 cities right now and a mobile version of the site for use on your cell phone.