I'm building http://test.gmbl.io as a side project - it'll be a nice stats site, I mainly built it for my own use and then decided to make it accessible on the web, rather than just replacing my spreadsheets. Might monetise it eventually, but I just want to finish it off in the end.
(Excuse the designed-with-a-potato look, the prototype designs are at http://test.gmbl.io/static/prototype/1/index.html though!)
Edit: worth pointing out, I learned to code building this the last 4/5 months in my spare time.
Double edit: Eh, it's pretty clearly Definitely Not Finished. Lots of placeholder text and stuff, but yeah.