If you love Snoopy, or the Peanuts in general, you absolutely MUST visit the Snoopy museum in Tokyo.
I can't even begin to imagine the work that goes into the exhibits here. The entire museum's presentation changes every 6 months. Not only in the exhibition space, but also about 80% of the merchandise in the retail store. Having worked in retail land wholesale for decades, I have to tip my hat to these folks for pulling all of that off.
Also, don't skip the cafe. It is absolutely adorable with a menu that borrows heavily from the themes in the comic strip.
Very well worth your time and money!