I have a couple of old slate format Tablet PCs that have outlived their batteries. So they are no longer portable, but other than that just as functional as they ever were.
I have parked one on the corner of the desk where I most frequently jot down notes by hand. I have it running Windows 7 and OneNote (desktop version) and I no longer have to pull the Surface Pro 2 out of my bag to make a quick note. And because the OneNote file is on OneDrive, my notes are accessible everywhere.
This is great.