Have you ever heard of SketchCrawl? I found out about it today. And took immediate action :)
The 29th edition will take place on 16th October, so it's almost no time left to organize a great bunch of people but facebook has been invented for cases like this, hasn't it?
Visit the SketchCrawl web site to find out if your town takes pa2rt in it. If not - organize it. It sounds like a great fun.