The thing is that guys from sigor ros playes differently from Jimmy page... Jimmy kinda hammered/ slapped his strings, and it's didn't really sound too good...
The guy from sigor ros, on the other hand plays his guitar like you would a cello... but he also uses loads of echo...on one of the sigor ros forums it said he used microphonic pickups, but when I watched them live on mtv2, I saw normal pickups on an old gibson... and I think that bridge was normal as well...
personally, I'm getting a Rosin bow (cos nylon ones are crap sound wise, and horsehairs cost too much)... it's meant to be good on thinner (guitar) strings... YOU have to increase the tension in the bow though (that's what I've been told anyway)...
I really like that deep almost guttral guitar sound the guy from sigor ros gets... I've Ageastis byjrian (sp), and it's just a brillaint album.