Nintendo · 1999 · Nintendo 64
A writable magnetic disk drive that bolted to the underside of the N64 — announced in 1995, delayed for four years, sold in Japan only to subscribers of an internet service, and discontinued inside fourteen months.
The 64DD ("Disk Drive") was Nintendo's answer to the central limitation of the cartridge: cartridges are read-only and expensive per megabyte, while the CD-ROM its competitors had adopted was cheap but slow and equally unwritable. Nintendo's solution was a proprietary magnetic disk holding roughly 64 megabytes that the console could write back to. That read-write capability was the entire point. A 64DD game could store far more than a cartridge's battery-backed save, which opened the door to creation tools, persistent worlds, and content that grew as the player used it. The hardware was announced in 1995 and shown at successive Nintendo Space World events, then slipped year after year while the N64's own commercial window closed around it. When it finally arrived in Japan on 1 December 1999, Nintendo did not put it on shelves as an ordinary accessory. It was distributed through Randnet, a subscription online service run as a joint venture with the recruitment company Recruit: subscribers received the drive and a modem and paid a monthly fee for network access, a browser, email, and disk-based software. Estimates of the subscriber base run to roughly fifteen thousand — a rounding error against an installed base of tens of millions of N64s. Nine disks were released. Most of them are strange and interesting rather than substantial: the Mario Artist suite of painting, modelling and animation tools, SimCity 64, Doshin the Giant and its expansion, an F-Zero X Expansion Kit that let players build their own tracks and save them to disk. The service was shut down in February 2001 and the hardware discontinued with it. Several major titles conceived for the drive migrated elsewhere — most famously the expanded Zelda content long promised as "Ura Zelda", which eventually reached players as the GameCube-era Master Quest. The 64DD is the clearest surviving evidence of a version of the Nintendo 64 that was designed around user-created, persistent, networked content, several years before the industry had any of those things.