Building a Sentry Starship to go with your fleet. You only need one - and they're energy intensive.
Additionally, in Classic, you could queue up multiple of the same ship in a repeating queue, so it'd go, in a loop:
Fighter Bomber Bomber Bomber Missile Frigate - Fighter Bomber Bomber Bomber Missile Frigate
Since there are more Bombers in each loop, it prioritises those. Of course, you can set a dock to build just those, but then it won't contribute to any other ship. Using that, if it has to build all three, it'll get the Bombers out first, while still contributing to the others.
It's...not something I recall using intentionally, but something I have memory of seeing in action when I caused it by accident. I did go on and confirm this is a thing.
