As folk say we have moved on, as an ex-teacher I love Risc Os and my Iyonix but you can't convince people that 'Acorns' are serious machines. They are kids' stuff, and after you are old enough to start work then knowing about them is embarrassing.
Some years ago I suggested to the then current new risc management that the logo could be Ouroboros. The mythological serpent which continually swallows its own tail and is continually reborn.
Well it amuses me anyway!
The snake forms a circle so could be used in place of O, and snakes aren't 'Kids' stuff'