Weird Physics Units

First prize in Nick's Weird Physics Units contest goes to:

fb⁻¹

The Inverse Femtobarn!

The "inverse femtobarn" (fb⁻¹) is a measurement of particle collision events per femtobarn. Inverse femtobarns are often quoted as an indication of particle collider effectiveness.

It took Fermilab over a decade to achieve 1 fb⁻¹.

A close second was the shed, which is equal to 10⁻²⁴ barns or 3.86 x 10⁻⁵⁸ square miles.
Third place goes to the einstein, which is a mole of photons (6.022 x 10²³ photons) .
Honorable mentions go to the henry, zeptoweber, and of course, snap, crackle, and pop.