Well, at the risk of confirming myself as 'not cool' I have an 08 GT Sanction and I really like it. I bought it for £1550 from Paul's Cycles to replace my Giant Reign when it was nicked. The original rrp was £2500 but I don't know if anyone actually paid that!
While the price was a strong attraction given the spec, I also did a fair bit of research - there are some pretty positive reviews on the internet. Having ridden it for a while now, I think it's great fun and I honestly can't tell much difference in the suspension feel from the supposedly more advanced maestro system of the reign.
The frame is stiff, nicely made and has good do-it-all geometry. The suspension runs on headset type angular bearings that are easy to service and replace yourself.
GT don't make the sanction anymore but still make the force, which is very similar but has more XC geometry - which I've never really understood. I also like the fact that you don't see many others about on the trails although I probably hadn't noticed that this is because everyone thinks they're rubbish....