Real, Reversable, Barrier-Free Male Birth Control?

A few researchers who started aiming ultrasound waves at rat testicles may have figured it out:

The intensity of ultrasound required would be similar to that used to break down scar tissue after a sprained ankle, for instance. “Our long-term goal is to use ultrasound from therapeutic instruments that are commonly found in sports medicine clinics as an inexpensive, long-term, reversible male contraceptive.”

Ultrasound was tested briefly in prostate cancer patients in the 1970s, who described the treatment as painless and producing a gentle warming sensation. “It would be like sitting in a mini hot tub once every six months,” said Dr Tsuruta.

I think I could handle that.