I was never really a big fan of the neo-classical shreddery (Vai, Satriani, Malmsteen). It's certainly impressive, but it never really seems to go anywhere for me. I love a good heavy riff that you can sink your teeth into and just bounce around on, mostly in metal:
High on fire: Heavy but with a purpose
Mastodon: Fucking Riff-tastic, and pretty goddamned impressive
Kalas: Slow and Doom-y
SkeletonWitch: Blackened Trash Mastery
Mountain Witch: Fucking sweet stoner/groove