The trick is to justify buying one for your business, and then using it yourself after hours.
As a business asset, it has paid for itself fivefold in less than a year. As an employee of said business, i have unlimited access to a machine that I could never personally justify the expense of.
My laymans assumption is that acupuncture likely has a counterirritant effect, which can make pain seem less pronounced.
Sort of like how punching yourself in the side of the head can provide relief for a migraine.