Penn’s 4:20 Club has unveiled this year’s T-shirt design for 4/20, which has become something like the one day Mardi Gras of marijuana. You don’t have to be an Ivy League stoner dress like one. You can order one HERE.

RELATED: Gov. Brian Schweitzer vetoed a bill on Wednesday that would have repealed the state’s voter-approved medical marijuana law. Mr. Schweitzer, a Democrat, vetoed the Republican-backed measure along with several others he called “frivolous, unconstitutional or in direct contradiction to the expressed will of the people of Montana.” MORE

RELATED: Arizona’s medical-marijuana law takes effect today, but patients already have been lining up to pay hundreds of dollars in some cases for pot recommendations from clinics that opened in recent weeks for just that purpose. Health officials are concerned that so-called certification mills could quickly turn a medical program into a recreational one, but they have limited recourse. Starting today, people can apply with the state Department of Health Services for permission to use marijuana to treat debilitating medical conditions, including cancer, glaucoma, HIV/AIDS and Alzheimer’s. The online-only application requires a photo of the patient, a copy of his or her driver’s license, a signed statement promising not to give the marijuana to anyone and certification from a physician that the patient would benefit from using pot. MORE