This industrial chewing gum removal machine, which dissolves gum thrown on the ground by self-loathing cretins, has an $8000 price tag. That seems awfully steep. I'll bet someone could make an effective gum remover and sell it for a profit at $500. (Even cheaper, theme park and shopping mall owners could simply purchase a gun for less than $100 and shoot the morons who spit their gum on the ground.)
Link (via Pasta and Vinegar)