Imagine a tub overflowing with bubble bath, except it’s a club dancefloor and music is pumping all night. This is what is known as a “foam party” — a wild and exciting concept that nonetheless many are yet to experience. The concept exploded in popularity in Ibiza in the 1990s, and foam parties are regularly held at nightclubs and festivals the world over. Foam is generated with the obviously-named foam machine, and these can be readily purchased or hired for anyone wishing to host such an event. However, that’s not the hacker way. If you’re a little ingenious and take heed of the safety precautions, here’s how you can do it yourself. If you’ve ever blown bubbles, you’ll be familiar with the basic theory. Create a soap film across an opening, and then blow air through, and it’s possible to form a bubble. Foam is created the same way — it’s just millions and billions of tiny bubbles all stacked together. To generate a foam, we essentially need to blow loads of tiny bubbles all at the same time. Instead of a single bubble wand formed out of a loop of wire and dipped in soap, we need to create something much smaller, thousands of times in parallel. It’s the FPGA of bubble blowing. ...