March 21, 2026
Two bytes, one internet brawl
Storing 2 bytes of data in your Logitech mouse
He hid 'hi' in a mouse — fans cheer, skeptics cry AI, jokers want mouse RAM
TLDR: A hacker hid “hi” in a Logitech mouse’s DPI memory so it travels between PCs, and the internet erupted. Fans praised the pure curiosity, skeptics accused the write-up of sounding AI-made, and jokers joked about “mouse RAM” — proving tiny hacks can spark big debates.
A tinkerer stuffed two bytes — the word “hi” — into a Logitech mouse’s memory by sneaking it into the DPI setting, which stays saved when you move the mouse between computers. It’s gloriously pointless and totally delightful. The code is open-source — check out mouse-fs — and the comments turned into a mini circus. One fan summed up the mood: “To learn how to do it!” That’s the vibe — curiosity first, practicality never.
Still, drama found a way. A skeptic barged in with a sharp side-eye: “Written by AI?” They flagged the poetic line about “how far in I could get” as suspicious, turning a cute hack into a who-wrote-it whodunit. Meanwhile, the jokes flowed faster than a double-click. One commenter quipped they’ll “buy mice instead of RAM,” because who needs memory sticks when your pointer can carry a secret? Others cackled at the detail that macOS quietly drops the bigger messages this hack originally tried to send — like the OS said “nope” and walked away. Techy bits aside, the crowd split into two camps: those applauding the art of doing something “useless” just to learn, and those sniffing for AI fingerprints. Either way, the real payload here isn’t two bytes — it’s the comments, where curiosity, skepticism, and pure meme energy went full click-war.
Key Points
- •A Rust tool enumerated 33 HID++ features on a Logitech MX Vertical mouse.
- •HID++ 2.0 maps stable feature IDs to device-specific indices and uses short packet exchanges for calls and responses.
- •macOS’s IOHIDManager blocks longer HID++ report formats needed for certain writes (e.g., to a 0x1c00 feature), though IOKit may offer a workaround.
- •The device name register accepts write calls but does not change the reported name.
- •The DPI register accepts any 16-bit value and persists across computers, enabling 2 bytes of cross-computer storage; code (“mouse-fs”) is available on GitHub for Unifying receiver mice.