I couldn't help but post this. Well done to @francescomugnai

http://blogof.francescomugnai.com/2009/11/the-80-best-guerrilla-marketing-ideas-ive-ever-seen/

My favorites:

• BMW checkmate 
• Rubber ducky: though I wonder how effective it is because I don't know what it's selling. Hm...
• Urinal soccer goal 
• Homeless man: "Before you turn away, put yourself in my place" 
• McDonald's coffee & their large marketing budget
• Barbell in train
• Bounty ice cream

I'm most impressed by the interactive marketing shots.