Alot of the sororities on my campus are doing jungle themes. Need I say more?!?

7 deadly sins is good, pimps n hoes is always fun, naught school girl/perverted professor is good, Beer Olympics, Money can buy me love (give the girls money and then make the guys "earn" it then after a few hours have some girls set up with body shots etc that the guys can 'buy') , Around the world (have people set up stations with different shots/beers/drinks to shoot/pound etc, and give thema fake passport and the first person to get all the stamps gets a prize), splash bash (requires kiddie pools in your living room), wife beaters (everyone wears wife beaters, its easy and fun), pirates and wenches, jocks and cheerleaders, etc

Some I haven't seen mentioned...

Freaks and Geeks
Slip 'n Slide (these are always fun just get a couple of rolls of plastic sheeting soak em in water and soap and slide! if you have a hill it helps a lot)
Party in the ER (Diry Doctors and Naughty Nurses)
Mafia
Greek Gods (normally winds up being toga parties, but some people get creative)
Everyday is a Holiday
Barbie and Ken
Nuts and Bolts (guys get bolts, girls get nuts and you have to find your match)
Hayride
Twister (like the game)

Hope those help someone.

AVALANCHE!!
 

Have an Avanlanche Party. We did and it went off well, although there is a lot of clean up.

You'll need quite a bit of the styrofoam packing peanuts. They come in tubes, and there's more in there than you'd think. Drag them into the house, then bust 'em open and bring on the guests. (you wont get the right effect unless the peanuts are about mid-calf deep). We had around 500 people in our house at once and the flyers are still up on campus! (The party was almost 2 years ago!)

Also, we have our "Anything for a Dollar' party.

Print up 'dollars' and give them to the guys, or girls (whichever serves your particular needs).

The girls (or guys) that aquire the most dollars by the end of the night win prizes. Usually a mall gift cert.

Ideas
 

My friend's sorority is doing a jungle theme. All the guys are going to be dressing up Tarzan looking outfits and the girls something like Jane. There might even be monkeys.

University of Nevada - Las Vegas
Alpha Xi Delta
Iota Epsilon Chapter

My boyfriends fraternity (sig ep) had a really fun party, hicks and thugs, everyone dressed up either hicked out or thugged out and different rooms, or floors played either country or rap/hip hop, it was really cool to see what everyone picked to dress up as