The unit of resistance is the Ohm and it is notated by the Greek letter Omega.

Back in the day, (this is the early 1970's that BaronCarlos is talking about.) A bunch of physics students at Drexel University were protesting the Vietnam War.

Of course, pure science majors tend to be quite eccentric and like to stand out in their own special geek way.

Instead of carrying around placards of "Stop the War", or "Love your Neighbor", and etc, these students carried around signs with just the Greek letter Omega.

When non-geek mundanes questioned the content of the protesters. The Physics Geeks responded,

"We're the resistance dude!"

and started chanting