As spotted by SuddenDesu on Twitter earlier this week, an extremely rare and undumped piece of Mega Drive software called WonderMidi has just gone on sale in Japan on Yahoo Auctions for an eye-watering price of ¥999,900 (roughly £5,462/$6,765).
Wonder Midi was a Victor-developed program created for the special Mega Drive/Mega CD unit The Wondermega (initially released in Japan in 1992). The software was essentially a music program that allowed players to control various MIDI instruments via a controller plugged into The Wondermega's MIDI port.
It originally retailed for ¥9,900, according to an article in Beep (accessed via Sega Retro), and was only ever made available in Japan. As such, it's incredibly rare to see one up for sale.
The listing on Yahoo Auctions includes the cart, manual, and original box, but is missing the supplementary CD Wonder MIDI Collection, which featured additional 12 MIDI tracks to play on the machine.
Here's a link to the auction page. If you're based in Europe (or anywhere subject to GDPR regulations for that matter), you will need a VPN to view the full listing.