What a drag it is getting old

[gritsinmisery.livejournal.com]

Okay, help!  Very recently, somebody posted something -- a picspam, I think -- and in the comments I squee'd something along the lines of "Thank you, thank you, thank you.  I've been looking for an ep with smelling salts in it / You've just shown me something I can use for a fic for a prompt I haven't been able to work with."

Who was it, and what episode was it?