I've been playing with the Tidewater Area Naval Gamers (TANG) off and on for a few months now--one of the best features of this club are the large multi-player games this outfit runs under the sage tutelage of Ryan Schultz. We typically play tactical naval and air games. Now, there are a lot of multiplayer games out there...especially in the strategic realm. But we don't play any of those. Not that they aren't fun--they are, but it's hard to finish a war in an afternoon. Typically, your average session of THIRD REICH or EMPIRES IN ARMS or even DIPLOMACY takes a long time to play. And we all know about the "spoiler" syndrome--somebody on the losing end of the stick decides to do something totally inimical to their interests just to make life hell for a specific personality in the game. I was accused of favoring playing Italy in five-player THIRD REICH games just because (1) there was little real responsibility (after al, Il Duce was rather reckless in his foreign adventures), and (2) one could hold Germany pretty much captive for BRP loans...with friends such as these, who needs enemies, huh?
But the tactical games in a multi-player format are great. One, they tend to be short, depending on the system/scenario you are playing. We do naval and air games...and typically the action never lasts beyond a full day of playing--and is often far shorter than that. We play ancient naval tactical warfare (Avalon Hill's venerable TRIREME) through sailing ships (Clash of Arms' CLOSE ACTION and scenarios out of the two supplement books), Civil War (Yaquinto/Excalibur's IRONCLADS and IRONCLADS EXPANSION), to World War II (mostly Jack Greene designs--ROYAN NAVY, DESTROYER CAPTAIN, IRONBOTTOM SOUND II, etc). For air games, it's been AIRFORCE/DAUNTLESS although we're trying to "graduate" to J.D. Webster's FIGHTING WINGS series. We'll see how that goes.
Why are these games so great for clubs? For one, you usually enjoy a great deal of flexibility. There's typically a lot of different schenarios to choose from, depending on the number of people that turn up to play. Secondly, turns generally go a lot faster than for the strategic games (in general). So you typically aren't waiting around a whole lot before thinking about what you are going to do or to execute your moves/attacks. Thirdly, it's easy for novices to envision what is happening and to get quickly involved in the game with the minimum of knowledge/rules exposure. Everybody has seen Hollywood movies and knows a few basics about what a player should generally do (or at least they THINK they know). And, as I've mentioned, you play to conclusion pretty darned quick.
The experience is usually easily remembered and stories abound about how the action went. Kibbitzing during the game is fairly frequent, usually regarding historical trivia or tall tales of tactical engagements in past cardboard battles. And that is perhaps the best part of this kind of gaming. There's a huge amount of social interaction. Club members generally get to know each other pretty well in a short period of time.
So while I do love the strategic games (two player or more), the operational-level campaign games, the two player tactical games...it's the multi-player tactical games that seem to be the most flexible and the most fun for clubs.