I think that product is called Dr. Ferd's Wart Remover, something or other. Another way is the route I took in a couple of my racks that have several warts for power - some of the inexpensive surge protected power strips are made with the sockets crosswise of the body of the strip - I found some strips with 7 outlets, spaced so that you can plug in warts to sockets 1.3.5.7. This costs about $7 per strip, in one rack I mounted 4 of these at the bottom rear, staggered so that the cords from one set of 4 warts went between the warts on the adjacent strip. There's not much power consumption involved, so you can plug several of these strips into one strip and switch it all from one switch. I built in light switches into the bottom kick panel and built custom guards so they couldn't accidentally be turned on or off, then tied all the strips into that switch.
The one thing you need to be really careful of, is getting any audio cables close to one of those wall warts. Most of them are not shielded well at all, and I have had an 18 inch shielded phone cable pick up enough hum from a wall wart to make the entire system un-usable. The way I get around it is when I wire a rack I designate one rear rail as power/midi, and the other side as signal. If I have to switch sides with a power cable, I do so as much at 90 degrees to any audio cables as possible, and get it into the power bundle as soon as I can.