Photohippie wanted us to continue our discussion, but Grandpiper made a good point that the comments would be irrelevant to the Instructable and would clutter it all up. I figure that in a forum we can get more ideas on the matter, and I think it's something worth discussing.

What was said so far...
GrandPiper says:
I always wanted to do this with marijuana seeds. They grow fast and can survive under pretty harsh conditions. Im sure they would get pulled up eventually but if you hit enough spots with them and planted close to 20 or whatever a spot, i think it would really send a statement to your city. I wanted to do it preferably in the downtown area, add some green life to the dead concrete jungle.

Valche says:
Usually I try to leave positive comments, but that's a stupid idea. I'm all for legalization, but planting pot isn't going to make any statement other than "Wow, some pothead thinks they're cool."

GrandPiper says:
Hmm what's your idea then? Writing your politicians so they can blow us off for lobbyists? How is my idea much more different then marching in the streets? The guerrilla growing is a way to say "hey i dont think smoking marijuana is as bad as other legal drugs" and it also doesnt expose yourself to the police as a marijuana smoker. This can be done in the cover of the night and you could carry a lot of seeds without being noticed.

Sorry for posting a response irrelevant to the instructable! and Valche if you want to discuss this further, send me a pm.