Here is how I made a Knight Rider T-shirt with flashing LED and theme music. Why? Well because I liked watching Knight Rider as a kid and I haven't seen anyone else make one like this.

Step 1: Materials

- The 8 LED scanner light was found here http://www.knightlight.co.uk/pr-ks5008.asp? I bought the unassembled version so that I could bend the LED's around the board.

- The shirt was made from a graphic I "found" online. It was re sized so that the LED's would be proportional to the car. I had it printed through an online t-shirt printing store like CafePress.com. Sorry, I can't share--copyright issues and all that.

- The sound recorder is not very loud but adds a nice touch. It came from Radio Shack. http://www.radioshack.com/product/index.jsp?productId=2102855

- Wire and two 9 volt battery connectors
- Gorilla/Duct tape
- Plastic card
- Hot glue
- Scissors

Step 2: Assembly

Assemble/solder the LED's scanner per the instructions but leave just enough room on the LED leads to bend them over flat as seen in the photo.

Carefully cut the LED scanner section out the shirt out.

Cut out the same area of a plastic card or other ridged mounting material you want to use.

Hot glue or fabric glue the mounting card to the shirt and trim as necessary.

Cut and rewire the 9 volt battery wires from the scanner and sound recorder down to your pocket or other battery holder.

I thought the LED's were too bright. To tone them down I painted them with red model paint.

Download the Knight Rider or KITT sound track of your choice and record it on the sound recorder per instructions.

Duct tape the scanner and recorder to the plastic card any way you can. Mine is not pretty but it works. You can't permanently connect them because you will eventually have to wash the shirt. Seriously. Wash your clothes. Girls can get over the Knight Rider obsession, but not the stink.

Step 3: Finished

You can use some duct tape to feed the battery wires down your shirt and into your pocket. I was thinking about using conductive thread but not sure if it can handle the voltage. I was also thinking about making a fancy battery box with on/off switch. But for now, plugging them in my pocket works fine. There is a little video attached to see and hear it in action.