Heard in a meeting. Apparently not new, but new to me. The meaning was fairly obvious from context. Definition from the Jargon File:
[Cisco] A command in a complex piece of software which is more likely to be used by an extremely experienced user to tweak a setting of [...]

Around 1992, I started using the term “reverse defenestration.” I no longer remember whether I’d heard anyone else use that term previously. Example usage: “I reverse defenestrated that PC, and now it is faster and more reliable.” Such an upgrade is most commonly from Windows to Linux or BSD.
reverse defenestration /rɪˈvɜrs [...]

In response to one of my recent dreams, Richard wrote:
I hereby decree that, henceforth, the expression “leaking blue liquid” shall be mean “I did something wrong, but I don’t know what it is.”
Examples:

“I seem to have leaked blue liquid in the boss’ office.”
“I’ve been trying to clean blue liquid out of my computer all day, [...]

Seen on a forum:  [someone] might get a wild hair up their alien probe-hole

To my rant on the CBS evolution survey, Tsar Chasm posted a response that is a snowclone, of the form: X make(s) baby Y cry.
All your snowclone are belong to us!
I, for one, welcome our new snowclone overlords.