Because most of the games I play in are late night, I just go home after the game.
Best bet is to find two board games as most I've seen only go up to six.
Movies are a good bet.
An all night eatery is another good one. Nothing like bugging other people at 2:00 AM or so. Usually you get to see a lot of drunks trying to 'sober up'. (Been there, done that.)
Anarchorism is a fast paced card game for 2 people but it's only 5 minutes so you could swap out every few games for someone else's enjoyment. Non-collectible, but collectible in that it has like 16 expansions so far. Good stuff but a little pricey.
Card games, like Poker or Crazy 8s, Blackjack, etc..., can be played with a large number of people.
Heck, get some paints and do a paint day. It's always cool to test your skills against other painters. Do some speed painting or all paint the same figure and see what shakes and what works.