Callsigns were always a good laugh way back during RAAF huey bush-pushes. We would make up funny formation callsigns in the TACP - it also pissed off the grunt commanders which made it more fun.
(Arm-Out-The-Window and Capt Sandune would recall well!)
The boys would delight in checking-in RT with: 1 potato...2 potato..3 potato...4!