While Tokyo is much cleaner than other big cities I’ve visited throughout the world there is still plenty of street art and graffiti to find if you know where to look for it.
I went out exploring over the weekend for an hour or two in Shibuya-ku (Ebisu, Hiroo, Daikanyama) and found plenty of examples. There was some really cool stuff but sadly plenty of just messy scribble tags as well.
I get some ideas from the really good stuff when it comes to graphic design. Most of the street art is garbage but when you find something that looks really great it can be a moment of inspiration.