I may be less insane in terms of size, but the availability of 30x40cm (about 12x16") puts it in it's own class of insanity. The only cameras I've seen are variations over the Russian plate cameras like mine - big, heavy, ugly folding "field cameras" weighing in at 15kg (32 lb) and up. The (plate, not film) holders that are all that's available are also so heavy that I'm almost glad I have only one.
I have a Rusky 30x40 but it only weighs in at 23 pounds. I thought we had the same camera but maybe they are different. I'de like to see some pics of the one you have. Mine is clunky but it is mahogany and has huge leather bellows on it. The plate holders add a bit of weight. The availability of film is poor but I have a few hundred sheets of Russian Pan film along with some Agfa Aviphot 200 and I even have some color Fuji NPL in 30x40 size.