There's solid evidence from its success on other platforms that Skyhook's unique WiFi-based positioning system makes a big difference in GPS usability on handsets -- and if you're looking for it on your Nokia, your moment has arrived. Maps Booster for S60 runs quietly in the background, augmenting the phone's built-in GPS capabilities to deliver faster, better results (theoretically, anyway) no matter what application you're using, which seems to make it a solid purchase if you spend much of your time trying to find your way through urban canyons, heavy vegetation, or some combination thereof. It'll be available early next week for $2.99.