The Gainamatsuri or Gainax Festival was a weekend long event sponsored by Gainax for its fans. The first Gainax Festival was held in March of 1994, at the Mikami Hot Springs in Gunma Prefecture. Numerous guests were invited, all of them being associated with Gainax in some way. A number of different events took place over the weekend including discussion panels, film screenings, karaoke, video game contests, and charity auctions. Apparently when the Gainax boys play, they play hard, in an otakuish sort of way of course.

The second Gainax Festival took place in July of 1995, at the seaside resort of Itako, Ibaraki Prefecture and was different to the first in that it used a LAN within the event site together with a BBS to create Synapse, an attempt at making a virtual convention space on the Internet in conjunction with the live convention site. This was more than six years ago, when the net was new and strange and wonderful and this sort of thing had never been done before. That is very impressive considering these guys are just an animation studio (though they do produce computer games).