For me, it's the Xbox 360 console. My favourite console of any generation. I also have over 100 original 360 and original games (backwards compatible) + kinect + guitar hero. I still play it all the time and don't anticipate ever replacing it. Even with newer generations of Xbox I find that the backwards compatibility is not comprehensive and has several limitations. Maybe I'm getting old but the last two generations of gaming have not really pulled me in and I don't really like where the whole industry is moving towards (online gaming, MMOs, casual games, paid DLC, HD "remasters" or "rehashes" of old games as I call them, etc).
I own 2 x 250GB slim consoles and 1 x black elite 120GB console. I bought some of them really cheap on the second hand market as people are getting rid of them. I know that eventually as the consoles pass the 15-20 year mark they will start to break down and become harder to find parts and/or replacement, and the prices will inevitably go up…time will prove me correct.
Hard drives for backups. Many many hard drives.
Consoles are all replaceable so not worried about that. There isn't much else I care for immediate resilience options. Duplicate keys I suppose?