Great Internet rabbit hole indeed…

Holy moley! (note the spelling) was Captain Marvel’s characteristic exclamation of surprise, and the strip popularized the saying among American youth, along with Shazam!

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But there is solid evidence that “holy moly” was already widely in use in the late 1920s as a jocular euphemism for “Holy Moses,” an oath that, at that time, might well have been offensive to some people. The writers of Captain Marvel simply picked it up and ran with it.

Interestingly, the spelling “moley,” which appeared in the very first issue of the Captain Marvel comic book, may have been influenced by the name of Professor Raymond Charles Moley, quite well-known in the 1930s as an important ally of President Franklin Roosevelt and organizer of his “Brain Trust” of advisors. Moley became even more famous after he turned against the New Deal and became a conservative Republican, and apparently there were political jingles and rhymes at the time coupling the name “Moley” with “holy.” Almost all modern uses I have found of the phrase, however, spell it holy moly.

via The Word Detective

My fav: with great power comes great grief

There’s much more greatness on his tumblr.

This guy definitely has it, holy molly!