very simple project--probably

And the sequencing should seem fairly random.

Hmmm, go to the dollar store and pick up a few 1$ fiber optic trees with RGB LEDs in them. These things cycle across all kinds of colors too. When you get bored of them, lots of parts are already laid out for you to tinker with.

Use a PIC, of course.

uC preferred but if that scares you then..

MLS (maximum length sequence) generator. This uses a shift register + logic gates. Use RC networks to get the glow effect. D from BC

Make up 3 or 4 strings consisting of LEDs (say 4 leds), a current limiting resistor and a "flashing" LED (the ones with the integrated flashing circuitry) in series. Put the 3 or 4 strings all in parallel. The flashing LEDs flash at a slightly different rate to each other giving a random flashing effect. "Mix" up the locations of the LEDs so they are not all in the same area / line etc. Works well for little christmas trees.

See how this goes:

|---->|---->|---->|---->|------>|----/\/\/\/---------| | | |---->|---->|---->|---->|------>|----/\/\/\/---------| | | |---->|---->|---->|---->|------>|----/\/\/\/---------| | | |---->|---->|---->|---->|------>|----/\/\/\/---------| | | | ^ | pos flasher gnd/neg

It worked for me, ymmv.