Getting all types that implement an interface

Question

Using reflection, how can I get all types that implement an interface with C# 3.0/.NET 3.5 with the least code, and minimizing iterations?

This is what I want to re-

Answer 1

loop through all loaded assemblies, loop through all their types, and check if they implement the interface.

something like:

Type ti = typeof(IYourInterface);
foreach (Assembly asm in AppDomain.CurrentDomain.GetAssemblies()) {
    foreach (Type t in asm.GetTypes()) {
        if (ti.IsAssignableFrom(t)) {
            // here's your type in t
        }
    }
}