As I was walking under the cherry blossoms in capri pants and no jacket (take that, Sweden!) I saw this sign on a lamp post. Kind of a nice break from ads and tragic lost kitty posters.
This seems to be a bilingual Canadian initiative, the small print says ‘http://www.somethingnice.ca/‘ you can download a sign and post it in your neighborhood. Maybe I will come up with a Swedish version to bring back with me.