They celebrated an anniversary a few weeks ago, with a buffet, drinks and belly dancing. It was fun: the food was good, the belly dancer managed to really engage the audience, and the people were interesting.
The bellydancer - Japanese, by the way, not Turkish - got people up and dancing along with the music. And no, it was not a costume party.
One group of regulars are military otaku, with an eclectic mix of mostly European uniform pieces - the pike helmets are Polish, apparently, and the white flowerpot thing is colonial British. One of them sported a monocle and an iron cross. We had no idea what they were about at first; Ritsuko thought they could be comedians still in stage costume, while I thought they might be right-wingers that'd lost their minds. But no, they simply dress up in uniform and meet over dinner from time to time.
As a fellow geek I certainly understand and sympathize with such an obsession in general, even while I'm firmly opposed to the tasteless idea of treating military items as something positive or worth glorifying.