Is it possible to define an anonymous implementation of IComparer?
I believe Java allows anonymous classes to be defined inline - does C#?
Looking at this code I
Take a look at these 2 SO questions, they tackle essentially the same problem
Use of Distinct with list of Custom Object
Wrap a delegate in an IEqualityComparer
If you go this way, you should pay special attention to Slaks' comments and Dan Tao's answer about the hashcode implementation