I tried yesterday. While there was coffee that was sizzling on top of the liquid, I'm wondering if it isn't just the oils from the coffee. The "boiling" was taking place at the surface, but only at the surface. There was also a thin film of oil on top. The oil is part of the coffee. I think it's where some of the bitter tasting alkalai substances are at (like caffeine). I suspect that rather than the water boiling, the laser was vaporizing the oils.
Yeah. I tried this with my new 1W Survival Laser 445nm. It didn't work! Barely registered 5 degrees. Thought I had a dud until I realized I was expecting way too much, thinking my laser could explode a digital thermometer... I wasn't even aimed at the batteries. :crackup: