Trivia is fun. I recently ran into some WDW CM's visiting DLR and they said they do trivia at WDW, too. So you might find some there, too. Assuming it works there the same as here, look for a pin turned backwards on a CM's lanyard rather than showing outward. That's generally the sign here for trivia or diamond trading.
I enjoy it because I'm a trivia nerd about both the parks and the movies. At best, I show off my nerdy knowledge and get to trade for a nicer pin. At worst, I don't get to trade, but I learn something new!
Many of the regular traders at DLR bring large, heavy trade books or pinfolios as they grab a table at rope drop and stay till 3pm. I'm guessing they use lockers to store them or they just leave after trading.
I started with just a small bag of traders the size of the 25th anniversary ones currently for sale at the parks:
That's great if you're mostly just walking around trading. But if I want to stay and trade for a while, I prefer having a larger selection with me, so I tend towards a nice medium sized bag that carries more but doesn't weigh me down too badly when I'm carrying it the rest of the day.
I think this one is still for sale at the parks - it's odd because the pages are backwards, opening outward rather than inward, but it's a great sized bag: