Global Million Marijuana March (<-- Link is to Wikia page). 1st Saturday in May, or that weekend, or thereabouts. Home page mirrors: 1. 2.
 
For 2007 GMM photos and posters go here.

The most up-to-date 2007 city list with report, photo, and video links is at

GlobalMarijuanaMarch.org/2007.php

See also: http://cannabis.wikia.com/wiki/Global_Marijuana_March_2007 

2007 photo gallery: http://gallery.marihemp.com/2007 - 2007 Posters. 2007 GMM-MMM media coverage in English.