[natnat]

The Minerals Management Service (now the Bureau of Ocean Energy Management, Regulation, and Enforcement) is a pretty good example of that as it is. It's in charge of enforcing environmental regulations and such for oil companies, but it's also in charge of collecting oil and gas royalties for the government. This is part of why oil companies have historically been so friendly with it -- they are somewhat interested in avoiding regulation, but they are even more interested in minimizing their royalty payments.