If you've seen my HTC EVO 4G vs HTC HD2 photos then you know that while the two phones look incredibly similar, they are different enough for their accessories to not be interchangeable.
But that didn't stop HTCPedia from taking an HD2 car kit, moving the microUSB charging port on the base of the mount (it's already designed to move from left to right), and breaking off one side of the silver holder grip to accommodate the EVO. The mount swivels and the NaviPanel app automatically launches when the EVO is docked.
This isn't on the same level of "Wow!" as the Palm Touchstone mod, but it's a nice solution for those waiting for the official EVO mount to be released.