Well the best ones i can think of two great ones worthy of mention.

At cedar point we were all walking to the car to smoke before we went into the park, and we walked under a big digital clock that said 4:20. We were happy.

The other day we were doing a roadie when we pulled up behind a cop car that said Seargent (or how ever you spell it) on the back, and the car number was 420, so it said Seargent 420. We were incredibly happy.