Pounce is always the first game that my husband wants to play when we have folks over, so I figured it was natural that it be the first game I recommend here. This is a fast-paced game that is easy to learn and will definitely break the ice if there are several members of your group who don't know each other.
There are commercial versions of Pounce under the names Nertz and Dutch Blitz, but they only accommodate 2-4 players. If you want to play a big game like we do, use standard playing cards. Be sure that every player has their own deck of cards and that each deck of cards has a different back. It will make it easier to separate the decks later. Pounce can be a bit rough on your cards, so I wouldn't pull out that souvenir deck you bought on your honeymoon to Niagara Falls. We usually buy decks from the dollar store for 50 cents each.
The short description of Pounce is that it is a game of group solitaire. If you know how to play the patience game Klondike (which is the version of solitaire found on most Windows-based PCs), then you are halfway to knowing how to play this game. Each player deals out a pile of 13 cards with only the top one face up. This is your Pounce pile. Then each player deals out 4 face-up cards that serve as the basis for the work piles. The object is to be the first to get rid of your Pounce pile by playing the cards on either your work piles or on the aces in the middle of the table. The twist that makes the game interactive is that each player isn't confined to playing cards on the aces from her own deck; she can play on any of the aces in the middle of the table as long as she follows the correct suit.
Since all players play at the same time, it can make for a hectic and funny game. It is great for loosening up new players, which is why I think my husband always likes to open the game sessions with it. I found a Nertz video on YouTube that gives a sense of the spirit of the game. You can't really see the suits on the cards, but it will give you a feeling for how quickly the game moves. In Party Game Central's entry on the game, it is noted that Pounce is usually a silent game. As you will see from the video, I think most people avoid that rule.
There is an official group devoted to the game called the National Nertz Association. Through their website I found that there are places to play Nertz variations online. If you use MSN Live Messenger, they have a version called Solitaire Showdown. It is only for two players, but you get a taste of how the game works. I say, if you are going to spend all evening chatting on an IM client, you might as well have some fun while you do it.
If you want to try something different after dinner with friends, I would say that Pounce is the first game you should learn. I have yet to meet anyone who is familiar with Pounce or any variation of it, but everyone I've introduced it to has loved it. If you have played this game, leave me a note in the comments section.