So you think you're a Lost obsessive? Well you'll know all about the Hanso Foundation then.
No? It was mentioned in tonight's Channel 4 Lost episode, when Jack and Locke are watching the orientation film in the bunker down the hatch. There's also been a Hanso Foundation advert running during ad breaks in the show on Channel 4 and E4.
There's more about the Hanso Foundation on Wikipedia and Lostpedia - it's part of an alternative reality game, apparently, cooked up ABC, Channel 4 and Australia's Seven Network to keep all those with theories about the show's mysteries on their toes.
If you want to know more about the ARG, check out The Lost Experience.
Oh, and that booked published recently by a character who supposedly died in the plane crash at the start of Lost series one, Bad Twin, is somehow linked to all this too.
Which all reminds me about a blog I read a couple of months ago about how the makers of Lost are breaking new ground with their online marketing/extensions of the show.
So are you prepared to get even more obsessive about Lost and play the ARG? Or are you with the guys on the I Hate Lost website?