Arma 2 and S.T.A.L.K.E.R: what are some of the best mods?

I just bought both games recently (for S.T.A.L.K.E.R I mean Shadows of Chernobyl, not the two sequels), and my understanding is that both have some pretty hefty and awesome mods, but I’m wondering which ones I should try first?

On a related note I’ve seen a bunch of youtube videos of a Star Wars mod for Arma 2 but I haven’t had any luck finding that one in particular, so if anyone has an idea of where to get it I’d appreciate. ^^

For S.T.A.L.K.E.R. I’d recommend the king of mods, S.T.A.L.K.E.R. Complete. It’s a complete overhaul with graphics/weapons/bug fixes/gameplay tweaks.

Holy crap, that is one hell of a mod.