My first useful abstraction, [ontime]. Built to start and stop sounds on beat.
Inlet 1 is a toggle, turning the beat counter on. Inlet 2 is the speed or BPM with a number atom. Inlet 3 is the amount of beats in a bar also with a number atom, so if you're working in 4 beats, it will output a bang on the fourth. I made an example file to explain it better, turn on [ontime] and start turning the toggles on and off, waiting for the downbeat.
There's probably a more elegant way to do this, but thought I'd share!