This is why I mentioned that it's not all low hanging fruit. Movie listings? Requires feed integration, handling a lot of data, non-trivial presentation. Same with weather. Getting a good weather app is not 10 seconds of coding. Some, like ip address, are simple things, but even so whatismyip.com built a huge range of products around that one simple service.

I always hated how weather sites could not just detect my approximate location based off of ip (eg weather.com) and required me to enter in my zip code, google fixed that.

http://www.wunderground.com/ has worked by geoip for a while now.

Pretty sure they got that after google. For years, wunderground was the best of a bunch of terrible web sites. They're still about 40% ads by pixel though, and have a hugely cluttered UI. I'll use them as a second step (Google's "detailed forecast" link) after typing "weather" into the chrome address bar. But broadly, they still suck compared to Google.

About a year ago I've built a small weather app which detects users' location using Geolocation API: http://wthr.in