My school liked using ones that looked like little knuckles. They had moulded grooves where you were supposed to rest your fingers. I was never given one because I apparently gripped my pencil correctly, but I had friends who used them and who let me have a go of them sometimes. They felt a lot more comfortable than the fat triangular ones.

Yes, there was a left handed version as well, but I didn’t see too many lefties being given them. Not sure if it’s because there weren’t many lefties, or if they didn’t need to use pencil grips as much.