Pulp Alley for me too.
Dave has come up with a system that is so easy and simple but also contains a universe of diversity and possibilities. The game is so playable and so easy to pick up (and teach). The stuff of greatness!!!
That said, when it comes to my other favorite era: spy stuff - For me it's 7TV and 7ombie TV for zombies. Mainly because, for these type of games I think they really capture the essence of the genera.