[pimeys]

Do you always need some lazy evaluation to arrive at the Y-combinator? It seems that even for the strict example a lambda was used to hold the recursive call evaluating too early.

Well, anyways, these are very interesting ideas to study and opened up some of the reasoning behind Haskell's laziness for me.

[grdvnl]

It doesn't have to be. The stricter version is called 'applicative-order' Y-combinator. The article talks about both versions as well.