At Play Festival, Peachi had one of these budget £30 bubble machines as part of the amazing disco tricycle. I had to have one! And I wanted mine to be portable. One day I will need to mount it on the back of a bicycle.
A good chance to learn some more electrical engineering, I changed the motor from 240 to 12v, added a 12v/24v switch and safely wired in a 12 supply. As it happens these things have a transformer already to drive the 12v fan, so it was fairly easy to change the motor.
This project has given a lot of joy to a lot of children.