I can't really remember how I got to know about this place, but I was intrigued enough to make 2 trips there during my last Tokyo visit (the first time it was closed). It's not so much the exhibition that was interesting but the building itself. It was a public bathhouse for 200 years until 1993 when they turned it into an art gallery for Japan's up and coming. You can read more about it here.
To be honest the gallery space is really small and might not be worth making a trip especially for that, but as the bathhouse is in the historic Yanaka district, it makes for an interesting stroll after that. Yanaka was very near where I lived before and I would often go there during the weekends alone just to check out the cats.(I've real potential to become a crazy cat lady). Besides the many many strays, there are also rustic cat cafes, shops selling cat goods and a cat art gallery. This was my all time favourite.
There are a lot of cool shops there too though they are a bit dispersed and hard to find. I'm dying to go to this hat shop next time I'm there.
Going out for a walk with my camera later to relieve some of the interview stress recently (I just had one with Japan early this morning). More photos soon hopefully.