It’s hard to resist playing with a good webcam experiment and Smoke & Mirror is an especially fun one. Watch your reflection form in tiny particles and then wisp away in smokey trails. It’s a fun to play with, but really tough to get a decent screenshot of 
Daniel Brown created it as a WebGL shader study and has left the source nicely un-minified to make it easy to poke around under the hood. He also has an earlier experiment called we are all made of stars, which explores a similar style of webcam reflection. The smoke version is definitely my favourite of the two. It probably goes without saying, but you’ll need a WebGL capable browser and a webcam to view either experiment. They won’t be much to look at otherwise!