I'm not exactly sure what you mean by *service*. [MyFonts.com][1] has an open tagging system that gives you a good idea of how others classify a given font. It also has a nice "similar fonts" module on the right side of the page that will help you make connections.

If you'd like to know how a font of yours fits into the bigger picture, you could upload it through their [WhatTheFont tool][2]. Then see what typefaces it points you toward.

Then there's always [Typophile.com][3] where you can ask the experts. You would likely get a better answer there, it would just take longer. [The Critique forum][4] would probably be the most appropriate for such a discussion.


  [1]: http://www.myfonts.com/
  [2]: http://www.myfonts.com/WhatTheFont/
  [3]: http://typophile.com/
  [4]: http://typophile.com/forum/1