What are your worst nerd lacunae?

Do you have an odd gap in your nerd-cred? Something that "every nerd knows" that you've just never seen? Or maybe a game that "every gamer's tried that" that you never tried?

I've got a couple...

• Red Dwarf - I know it sort of looks like Doctor Who, and it's a comedy, and that's about it.
• E.T. The Extra-terrestrial - Never saw it, never cared.
• The Fifth Element - Ditto.
• BECMI - I've played and loved Holmes, but never played any of the other "Basic" D&D boxed sets.

How about you? What iconic nerd-thing have you just never gotten around to?