Faceplate Facelift
Even though I don't live or work in a crime-ridden area, when I bought my Alpine head unit to replace the stock MINI CD player the only thing I didn't like about it was that the faceplate wasn't removable. It folds up and slides into the unit instead. That's cool and all, but a knowledgable thief will see that the face plate is there and know that the unit will work if he steals it from my car.
So, I figured that same knowledgable thief will also know that the stock MINI CD player won't work if he removes it from the car. The answer? Make my new head unit look like the MINI stock player!
First I bought a MINI stock stereo on ebay to cannibalize. I didn't want to use the one that came with my car because when I sell it some day I'll re-install it first. I took it apart to remove the face plate, which wasn't as easy as I hoped. Detaching the faceplate wasn't so bad, but then I had to remove the circuitry from the back of it. The hardest part was getting the body of the volume button off without destroying anything that I wanted to use later. I finally got it off and thought I had something I could work with. I didn't own a digital camera at this time, so I have no pictures of the disassembly..
Here's the faceplate before surgery:
First I needed to remove the pieces on the sides. So I got out my favorite tool -
the Dremel. 
I used the little sander drum with a medium grit to eat away the plastic that I wanted to remove. On the back of the faceplate I needed to remove a lot of the structural plastic in order to have it sit as flat as possible on top of the real head unit:
Zip zip went the Dremel:
Not pretty, but hey it's the back.
Then I glued in the buttons, the CD felt, a piece of dark brown felt to masquerade as the blank display, and added a piece of trusty duct tape to secure everything and prevent any scratching of the head unit:
Here is the final result:
To finish up: a small piece of velcro felt on the trim above the head unit, a matching piece on the back of the fake faceplate, and...
...the illusion is complete.
So whenever I park in an area I feel may be unsafe, I'll pull the "mask" out of the glovebox and stick it on. Sure it's silly, but it was a fun project.