present participle. Throwing "that's what she said" around like you're Michael Scott or it's TWSS Day.
Real citation: "alas, I’ve been teaching PE to elementary school kids all day. And I don’t think it’s all that appropriate to use TWSS with them, although there were more than a few moments in the teachers lounge I thought it to myself. Now that I’m out of school, there will be much TWSSing tonight!"
(Markus, Feb. 15, 2007, http://www.officetally.com/international-thats-what-she-said-day)
Made-up citation: "TWSSing in church is all the rage for hipster evangelicals and teenage punks."