Kings Cup the drinking game is great for a large group of people. It is also known as Ring of Fire or sometimes Waterfall.
All you need to start is a deck of cards, 4 or more players, and alcohol of any kind. The reason people like to play Kings Cup is that you can make your own drink, meaning the players control the intensity of their personal game. Also there is very little chugging, with only the ace card rule requiring it.
The basic rules of the Kings drinking game follow, but there are many common variations. The most common complaint against this rule set is that it uses the words whores and dicks to refer to girls and boys, and it has the jive for five rule variation which many people don't like. So if that offends, check out another kings drinking game rule variation set.
Basic Rules:
2 - you (choose someone else to drink)
3 - me (person who drew the card drinks)
4 - whore (girls drink)
5 - jive (perform one action, next person copies and adds a piece, 3rd person performs previous 2 plus their own, etc)
6 - dicks (boys)
7 - heaven (last person to reach up drinks)
8 - mate (choose someone who must drink whenever you do)
9 - rhyme (rhyme words around the circle - first person who can't think of any must drink)
10 - categories (choose a category - everyone names something in it and the first person who can't must drink)
J - never have I (say something you've never done, and anyone who has done it must drink)
Q - questions (ask a question, don't answer anyone's questions)
K - make up a rule
A - waterfall (person who drew card starts chugging, then person next to them starts, and so on - stopping chugging works in the same way)