Looks like some homeowners who sign deals to allow recovery of natural gas on their property may get "fracked":
http://energybulletin.net/stories/2012-05-20/how-fracking-mess-about-make-mortgage-mess-worse" onclick="window.open(this.href);return false;
"This salient fact comes from an article (PDF) written for the New York State Bar Association Journal by attorney Elisabeth N. Radow. Written in the form of an even-tempered legal brief, Radow relates one astounding finding after another. Perhaps most relevant to homeowners who either have signed drilling leases or who may be asked to sign them in the future is this: "Signing a gas lease without lender consent is likely to constitute a mortgage default." You read that right. Default."