Can you create a simple 'EqualityComparer' using a lambda expression

Question

Short question:

Is there a simple way in LINQ to objects to get a distinct list of objects from a list based on a key property on the objects.

Answer 1

This is the best i can come up with for the problem in hand. Still curious whether theres a nice way to create a EqualityComparer on the fly though.

Galleries.SelectMany(x => x.Images).ToLookup(x => x.id).Select(x => x.First());

Create lookup table and take 'top' from each one

Note: this is the same as @charlie suggested but using ILookup - which i think is what a group must be anyway.