I am more into traditional hex-grid games.  I think Norm Koger's the Operational Art of War series is pretty cool for those who want computerized version of traditional hex-based games portraying large forces.  I would say its editor is its strongest suit:  You can draw maps, customize units (assign equipments and so on), set map scales and turns, plus event editor to simulate unusual/surprise events.  However, creating your own scenario can be pretty time consuming and you need to run many tests to sort out bugs and find out AI glitches.

 

'Beer & pretzels' games are quite good, too, such as Risk and Axis & Allies.  I used to play A&A a lot, and the feature that I liked the most was having to take some time to ponder about how to spend my resources.  I got beaten up a plenty of times while playing Soviet Union; three Allied players (US + UK + Russia) vs. two Axis players (Germany + Japan), in which the Axis players have oftentimes outplayed the Allies because it was not exactly easy to coordinate three Allied players into one cohesive strategy.  Risk .... used to play that like crazy while I was living in a dorm.  It was spring break and my buddies and I had nothing else to do and we ended up playing Risk over one of their's Mac.  Few other folks from my dorm came over and started watching something.  Oh my ... they brought a bunch of porno!  It was a funny experience as half of us were trying to conquer each other in Risk, while the other half of us were watching porno.