Riding high on the hydraulic fracturing wave, Northern Oil and Gas went on a spending spree last year, snapping up properties in the Bakken and Three Forks plays of North Dakota and Montana. By the end of 2011, the company's proved reserves were up 198% from where they were at the end of 2010. This year, first and second quarter sales were up 151% and 99% year-on-year, respectively, as production was ramped up to capitalize on rising oil prices. And there's no sign of any slowdown. Northern Oil completed another 162 wells in the second quarter, bringing their total number of producing wells to 955, with an additional 150 in the works. -- N.S.