What should be a service?

[Glen Stampoultzis]

Was just wanting to get some peoples opinions on what sort of things should be made into hivemind services?

It seems to me that it would be pretty easy to go crazy and make all sorts of services but I'm thinking that would probably be a bad idea.  Where do you stop?  I'd be interested in hearing real life services people have created. 

Regards,

Glen Stampoultzis