As Mike says, "I recently visited an indoor flea market in southwestern Pennsylvania. Needless to say, I saw 'quite a few' of these. The best I can tell, the owner wants children on the bike for some reason."
I don't usually post the following: newspaper headlines, personal email, craigslist postings, unprofessional websites. I also tend to not crosspost things from other blogs, since I have so much unique material waiting for me to get to it.
Things I see a lot: silica gel "do not eat"; hair dryer labels; inside the bus "do not drill"; Wal-mart sign about IDs; coffee machine with "2" cup sizes; employees must "wash hands".