Auto-escaping every GET/POST input at input time was quite something. Also arrays being pass by value is a lot of fun to this day: $a = [1]; $b = $a; $b[] = 3;

Auto-escaping every GET/POST input at input time was quite something. Also arrays being pass by value is a lot of fun to this day: $a = [1]; $b = $a; $b[] = 3; var_export($a); And that you could pass by ref at call time to any function. That was also quite unique.