Yes, the title pretty much says it all; the link sent to me points to a page that does indeed relate the experiment of frothing up a nice-looking head on a pint of Guinness with an electric ultrasonic toothbrush.
More recently, Guinness introduced the “Surger”, a drink-coaster sized device that froths up a home-poured pint by using ultrasonic waves to release the bubbles. The Surger produces an impressive pub-worthy head in seconds (and a larger version is used in pubs that don’t have a tap line installed). However, it is available only in the UK (for the price of £16.99, or about US $35) and you have to use a special kind of canned Guinness that’s had more nitrogen forced into it.
We wanted to see if we could mechanically simulate the Guinness Surger’s effect and create an acceptable head of foam on a canned or bottled Guinness through other means.
On one hand I admire the curiosity involved in this sort of testing, but on the other hand, I just want to say, Ew. I hope that’s a clean/sterile toothbrush.