Ball point pen draws electrical circuits.

[rug]

[Callmecrazy]

1. Cool product...

As I am an electrician, I could get into a lot of mischief with that thing.

[rug]

2. It looks so easy they better keep it out of middle schools.

[hunter]

3. Seems like an awesome tool for playing with high frequency antenna designs.

For example:

http://en.wikipedia.org/wiki/Fractal_antenna

[Wounded Bear]

4. That's kind of cool...

but it's not the pen, it's the ink.

As an old engineer since retired, I wish we'd had something like that years ago.

[Brother Buzz]

5. We did have pencil line resistors

Although it had no practical use, it was a good tool for demonstrating resistance.

[Ptah]

6. What if I draw a capacitor?

[jmowreader]

7. Depends on how far apart you draw the two plates, prob.

I wonder if this ink sticks to glass. If so, they'd be able to also sell the pen to the lucrative market of people whose rear window defrosters are broken.