Quite a collection! Did you get them from a corporate selloff or something? You might already know this, but Lenovo had the rights to use the IBM logo on their ThinkPads for several years after the purchase, so there are a few models that have the big IBM lettering but are really Lenovo machines.
I'm also intrigued by Pinebooks and their open philosophy, but my tolerance for slow computers is low. I haven't used one yet, but System76 laptops seem like a good compromise between open hardware and modern performance.
I bought most before, I made a standalone POS/encrypted communications device using upcycled X series thinkpads for my fintech startup. I bought the newer stuff when I got there using my employee discount, which wasn't as much as I would have liked, but was what made me buy new instead of used.
As you can see, YC has a lot of other Thinkpad nerds, you also see them a lot at CCC conferences as well, they're like the AK47 of hardware:
I can forgive less than optimal performance for ergonomics for specific tasks, long writing sessions on Libre Office doesn't require much performance so I like writing on that old machine because my fingers can type so effortlessly and require less spelling corrections--this is the model I used during my undergrad. I'm willing to give the Pine a shot and I'm keeping an eye on the new pre-order.
I have machines with specific OS' and hardware to keep me on task.
I'm also intrigued by Pinebooks and their open philosophy, but my tolerance for slow computers is low. I haven't used one yet, but System76 laptops seem like a good compromise between open hardware and modern performance.