Yesterday, it was someone's pronunciation of the acronym QIFM (which was a new one to me). She had a very strong Southern accent, so I'll let you guess what it sounded like.
My coworker and I immediately looked at one another other as soon as it was said and had to bite our tongues to keep from cracking up in front of our visitor.
My field of work tends to be rather acronym happy, and I'll just say that some of those acronyms would be better left as initialisms.