Animated flames and smoke markers

Why all the things on a table have to be static? Why not to make some of them animated? Tempting...?

I decided to play a little bit with batteries and LEDs to make an animated smoke marker. To make the marker I used CR1620 battery and two pulsing LEDs - red and yellow.

Below you can see a simple prototype I made, however, there are couple of things to improve. Unfortunately, yellow diode does not shine as bright as the red one. I had also a problem with the switch (actually, in the movie you see below, the yellow diode didn't turn on).