Related to online commentary: implonkus is that feeling you get when you take a moment to organize your thoughts on a subject, then set the notions down as clearly as you are able, and the person who responds online starts off with "lol", uses "to" for "too" and ends every fragmented sentence with an emoticon.

The word itself appears to be a combination of "impetus" and "plonk"; the latter is a Usenet-born onomatopoeia for the notional sound made when someone is killfiled (i.e. added to a kill file, a Usenet-era ignore list).

First seen on the HBO Sopranos forum.