One of the coolest things I saw in Osaka was a monthly flea market held on the grounds of Shitennoji Temple. It's a pretty big temple so there were a lot of vendors. I spent the better part of the morning eating amazing food and browsing through old games and records, vintage clothes, and all sorts of other old stuff. I ended up getting some old woodworking tools, a couple of wooden serving platters, and a copy of Dragon Quest V.