How easy? How about no soldering or glueing? In less than 5 minutes, you can turn an ordinary frisbee into a toss-sensitive, self illuminating flyer for some late night fun... or freaking out your neighbors...

Watch the full video (1 minute, 20 seconds).

Step 1: Supplies

Frisbee, cheap plastic light up yoyo, xacto knife or sharp kitchen knife, small screwdriver...that's it!

You can also watch the video here and see the final result in action.

Step 2: Prepare the Frisbee

Start by locating the center of the frisbee on the underside (It's easy...just find the small bump from the injection moldiing process... you can't miss it =). Use an xacto knife or a sharp kitchen knife and "drill" a hole large enough to accommodate the shaft of the yoyo.

Step 3: Take Apart the Yoyo

Disassembling the yoyo is extremely easy. Simply unscrew the two halves, and you'll see that the shaft goes through some small metal pieces that serve as bearings that allow the yoyo to spin. Remove these parts off the shaft (They should simply slide off). Now, use a small screwdriver to remove the two screws from each half of the yoyo. This allows each half to be seperated into the plastic covers and the circuit boards that contain the LEDS and batteries.

Step 4: Remove the Shaft

The shaft will run through one of the plastic covers. A hammer and a couple of gentle taps will cause the shaft to fall out.

Step 5: Assembly!

Now, take the inner plastic covers from each half of the yoyo, reverse the circuit boards so they face outward, and place them inside the plastic covers. Place one of these new halves on top of the frisbee, and the other on the underside so they are centered with the hole you made in the frisbee. Insert the shaft through the top half, through the frisbee hole, and into the bottom half. Tighten the whole assembly by twisting the underside half, and it will re-thread onto the shaft. That's it!

The centrifical force caused by the spinning frisbee when you throw it will turn on the LED lights just like the spinning yoyo. The batteries will literally last for hours, and can be replaced simply by unscrewing the assembly.

The instructions may seem a little more difficult than it actually is, or might seem confusing.

This video shows the entire process, as well as the final product in action, and should clear up any questions you may have as far as the steps are concerned. Have fun!