I have one that was built in 2012. I added an SSD and run Ubuntu on it. You can get cheap and poor quality batteries off eBay. It was the first time I was exposed to the special Thinkpad black rubbery coating. Some people hate that color and coating. I fall on the other side.
Some people love the keyboard. I do like the feel and travel of it, but the keys are a bit noisy.
It’s also quite a small form factor - smaller than 13” even, which makes it look quite compact against a modern 14”
The form factor is great for writing on the train, but the screen and touchpad are a bit cramped for other work.
It is built like a tank.
I once walked through a downpour and water got into my backpack and then into the beloved X220. I didn’t notice until later in the day.
I turned it on and the whole display was flickering and there was a giant diagonal splotch on the LCD. I was devastated. I turned it off (it had been sleeping in my backback) took out the battery and put it my desk.
I waited 24 hours before plugging it in without the battery. The display had stopped flickering and the giant diagonal splotch was now a smaller splotch covering less than a quarter of the display.
The next day the splotch was even smaller.