Evidently it's not "too" illegal to smoke on the campus of the University of Colorado in Boulder on 4/20. About 10,000 students gather every year to celebrate 4/20 and light up at 4:20pm.  This is put together every year by students and has no affiliation with the school what so ever and cost about $50,000...get this, only about 10 arrest were made at the event!! See how it all went down!