Wax. . .

[proud2deviate]

Here's a fun little experiment. All you need is a relatively high-powered laser (I've gotten this to work with > 100mW of well-focused green,) and some appropriately colored wax (the darker the better.) Simply focus the laser on the wax. As it melts, it will become reflective. Angle the laser so that it reflects onto a wall, ceiling, etc. As the wax continues to melt, you'll see some pretty interesting shifts in the reflections. With higher powers, you might see bubbles.

For more action, you can rough up the surface of the wax to create little structures that'll melt and deform.

 

[magonegro]

I guess it'll be like when you burn some shiny surfaces, but may be translucent wax reflects little radiation making this less impressive. Anyway, may be some other materials could be used for this effect, I have here a little bottle with Gallium, (much less toxic than mercury) it is solid metal at room temperature, but it melts quickly at ~37C. If I have the time i will try to experiment with a 445nm to see what happens... I have tried the gallium for making front surface mirrors, and due to the little success it is kept in the shelf from years ago. May be finally I have found some utility for it? :thinking: