Two medical marijuana dispensaries in Los Angeles have installed pot vending machines. They're accessible 24 hours a day and monitored by security guards. From Thrillist:
After cinching up your doctor's consultation, hit an AVM location to get your prescription approved, fingerprint taken, and a prepaid credit card loaded with your profile: dosage (3.5 or 7 grams, up to 1oz a week) and strain preference (choice of five, including OG Cush and Granddaddy Purple, the mildly hallucinogenic forebear to Prince). Then day or night, all you do is hit a machine and walk away with enough vacuum-sealed, plastic-encapsulated cheeba to adequately treat your illness.