Balls Bouncing Off Each Other - Based On Hyperized Blocks

Not very realistic, but fun nevertheless.

The blue one has a slightly modified code TELLing the ball it is bouncing off to do the bouncing of its own. (I have tried to copy the code to all the sprites, but then each ball does double bounces, which is not good.) Any ideas?

Number the sprites, and in case of collision the lower numbered one is in charge?

What an elegant solution! I love it. Thank you!

I learned it from SICP. :~) It's a standard technique for avoiding deadlocks in databases and operating systems.