One of the things I loved—and still do love—about MiniDiscs is the whimsy they bring to my life. And this whimsy is no better illustrated than with TDK's "BitClub" line of MD media. I had a couple dozen of these back in the day and they were always my favorite.
Nowadays, if you're lucky enough to find any for sale, they are crazy expensive—which is why I don't currently own any. That top photo was from an eBay sale; $68US for the lot. That's $11/disc—half what you normally see them for—and still a price I can't justify when "regular" disks typically go between two and four dollars.
So unless I fall into a wad of cash, I'll just have to admire the whimsy from afar…