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.