So you're in a pug 25man. It's going slow. You're bored, you need a good guffaw.
This is a very simple trick, and it goes as follows:
/e prepares a Fish Feast!
drama ensues.
People will begin to look around for the fish feast, and will begin getting frustrated. They will yell at people to stop sitting on the feast. Pretty funny, makes pugs much more enjoyable.
Alternate approach - credits to Unholy[S]haman - If it is a multi-boss dungeon (E.G. not VoA) for the first few bosses put down real fish feasts. After three bosses or so, people will be expecting feasts before every boss. That's when you use your emote