A "rabbit start" is a fun alternative way to start a race, used exclusively here for Santa Cruz Wed, night races with a fleet of diverse size and speed. No RC necessary
A boat volunteers ahead of time to be the Rabbit, usually one of mid-fleet speed, not too fast or slow. Flying a distinguishing flag from the backstay is a good designation for the Rabbit.
A warning horn is sounded by the Rabbit 5, or 3 minutes, before the Rabbit starts its run. Another horn is sounded at the start when the Rabbit starts its "run," close-hauled, on port tack. You then have 5, or 3 minutes to start by crossing behind the Rabbit on starboard tack. In effect, this is a moving gate. When all have started, the Rabbit is "released", tacks to starboard, and the race is underway to the first (windward) mark.
The 505 Class uses the Rabbit start for all their races, even in the big fleets of their Worlds Championship.
One local variation is for the Rabbit to tow a rubber duckie 1-2 lengths astern. This helps prevent close encounters between any anxious starters and the vulnerable Rabbit. Another variation is for the Rabbit to start its run on starboard tack, and the starters cross astern on port tack.
Recommend giving it a try. Works even when 2 boats are "playing" together. Wouldn't work if starting classes at different times is desired.
https://www.youtube.com/watch?v=b7_MrijLSuE