Rainbow Pocket Lamp!

One of my friends mentioned how cool it would be to have colored smoke coming from an electric cigarette.
While that's impossible(without it being toxic), this is easily the next best thing!

I had a large bin full of new and used electronics, so I just followed ROY G BIV to choose my LEDs. I skipped indigo, and went straight from blue to ultraviolet.
The tricky part was digging through resistors, as each LED requires a different voltage.
I found the LEDs on Amazon and I acquired the resistors and screw terminals at my local RadioShack(yes, they're still in business).

I already had a pack of (cheap)PCBs, and the necessary tools.

The simplest way to explain this step would be to solder all the negative leads together, and put the appropriate resistor on the positive lead of each LED. After I had everything secured together I ran the main power rails to the appropriate point on the screw terminal.

After I had everything soldered together I couldn't help but power it up and give it a go!

Blowing smoke above the lights gives an almost hypnotic, color changing effect as it billows around.

A few things to keep in mind,

- I didn't post specific resistor values because it honestly depends on you input voltage.
I used 6v in, but had to drop it down to about 3 anyway, so you could actually power this off of two double or even triple A batteries.

- Your LEDs might have different power requirements, this is just a general proof of concept.