According to the Washington Post, couples who smoke marijuana are more mellow and less likely to engage in domestic violence [via JAB]:
A new study by researchers at the University of Buffalo finds a significantly lower incidence of domestic violence among married couples who smoke pot. "Couples in which both spouses used marijuana frequently reported the least frequent IPV [intimate partner violence] perpetration," the study concludes.
These findings were robust even after controlling for things like demographic variables, behavioral problems, and alcohol use. The authors studied data from 634 couples over nine years of marriage, starting in 1996. Couples were administered regular questionnaires on a variety of issues, including recent drug and alcohol use and instances of physical aggression toward their spouses.
The trouble is, smoking can lead to lung cancer. If you're going use marijuana, it's probably healthier to ingest it. There are loads of healthy (and otherwise) recipes at The Stoner's Cookbook.