I've found a new favourite artist today: Sean Murphy http://www.seangordonmurphy.com/
I picked up a copy of Batman: Twoface and Scarecrow: Year 1. His style graces the first set of stories in this collection (a few black and white scans of those pages are on his Batman art page). Then I noticed he also provided a Han Solo/Indy themed story for one of the Star Wars Tales volumes. His work is cartoony and aggressive and very recognisable.