It doesn't hurt to have some humor, especially in dark times like these. Businesses are always trying to one-up their competitors, and drawing up charts, presentations to reduce overheads and maximize profits. While business is, in fact, serious business, sometimes the best way of connecting with customers can be with humor. Some businesses are lightening up the moods of customers and staff with witty signs, offers, and ads. Here are 20 hilarious signs, ads, and scribbled notes that would've helped make their customer's day: