Software
Web MiniDisc
A online cross-platform web app, that acts as a frontend to Vuori's linux-minidisc tool. Requires a Chromium-based browser. Supports groups and full-width titles.
Zadig USB Driver (req. for Windows only)
Platinum-MD
Platinum-MD is a modern NetMD writing tool, using similar libraries as Web MiniDisc. Popular with Mac users for ease of install. At the time of writing has experimental support for Hi-MD, but lacks groups/full-width support.
Zadig USB Driver (req. for Windows only)
SonicStage
Sony's official NetMD software for Windows
Installation of SonicStage on a modern PC is possible, but driver install is a little more complicated.
SonicStage Digital Archive (Includes Ultimate, Japanese Releases, and Ultimate)
linux-minidisc
A reverse-engineered, cross-platform command line tool for NetMD devices. Allows full quality SP transfer over USB, unlike SonicStage.
md-rec
A Python-based tool that automatically records, labels and marks tracks on compatible Sony MiniDisc recorders without NetMD.
Requires a Raspberry Pi (or similar SBC) and a basic circuit to connect to the remote port.