I'm a fan of C# myself.  your *fastest* and easiest way probably is to just add it to the admin directory or to use the DNN solution and follow Michael washington's WSP for developing modules. 

but a skin object isn't too hard to do.  just as long as the dll gets dropped and its properly mapped in your database.  that's really it.

Oh yeah, how do you suggest we persist the breadcumb items that need to be shown as the user clicks. Session? Database? Maybe we can interpret it from the item that is selected.

Example: If we select product A that is in Category C which is a part of Category A we would get a breadcrumb like - Home > Products > Category A > Category C > Product A.

If we wanted to correctly map the user's clicks then we would need to persist it somehow.