I very often whip out this tried by true joke. People often think it's "just a joke", but I actually think of it more as an adage, as words of wisdom, that also just happen to be whimsical.
There are only 2 difficult things in computer science:
1. Naming things
2. Cache Invalidation
3. Off by one errors
The number of times I've told it in an interview with a programmer and they don't laugh are horrifying. There's deep, memorable wisdom in there if you have any experience.
