There's a double DIN unit with DVD & GPS fro Caradvanced.
Thread all about it HERE.
They signed up here as a vendor a while back & were selling them at a discount on a group buy. After the first group buy, they started a 2nd, but I am not sure if it is still ongoing. (There's a link to the group buy somewhere in that thread) I did a series of videos using a local guy's Caradvanced unit in his Mazda3. Very nice unit, retains all steering wheel controls, and the upper LCD display.
Edit: Group Buy ended June 17, but if you contact them quickly, I would imagine they may be willing to work with you.
Here is the group buy thread.
Here's a link to the Youtube video for Part 1. It's 5 parts, but the last 3 parts just cover the available GPS systems on the unit- you get to choose your GPS software.
The Pioneer AVIC-F series is also quite nice if you want a full function unit with GPS, DVD, etc. It just won't retain steering wheel controls without an adapter (available from anyone who sells the AVIC) and won't retain full function of the LCD display above. Early versions of the AVIC-F Series had some software flaws, but most of those have been worked out now.
Of course, there are dozens and dozens of head units out there, and it all depends on what you want them to do.
