The literature concerning students' understanding of the equal sign has focused narrowly within the context of formal mathematics. Researchers have put forth a hierarchy of conceptions of the equal sign with only the top level regarded as correct. Meanwhile, we find that the equal sign is used widely and in a variety of ways in advertising and social media. We use conceptual blending to analyze several examples of statements involving the equal sign, drawn from outside of school mathematics. We find that the hierarchy described in the literature is insufficient. Instead, we see the necessity for various interpretations of the equal sign as a matter of 21st century literacy. We elaborate on the implications we see for research related to the equal sign and for instruction.