Life as I know it wouldn't have come to pass without a computer, so I'm inclined to say that! Though, to say more on the subject...
I don't quite have a Book of Shadows set up yet, so that's a little embarrassing... Uh, opposable thumbs?
I think I'd also like to say my bike! I don't particularly enjoy driving much and when I go out it's usually up to hours that public transit doesn't run anymore, so having a thing for exercise and transport both is really convenient. Especially so when the library and a supermarket are just 10 minutes away by it!
I like my Flipper Zero. It's a cute little hacker device that can do all kinds of thing: Sub-GHz communication, infrared input/output, RFID and NFC read/write/emulation, bad USB (USB rubber ducky), and iButton read/emulation. You can even expand it with GPIO! I often have it with me. Maybe someday I'll find the perfect hacking opportunity :3
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