How do you (digitally) catalog the books you've read over the years?
I use a wiki these days! I've been using a personal wiki to collect notes about everything I learn, read and watch since last year and it's great. I've installed a DokuWiki on my personal website, and it's like my micro-wikipedia.

Installation is not complicated and anyone willing to tinker with tech should be able to find a way to get it working in a couple of hours. 

Before that, I've used Evernote, and also note taking capabilities of my kindle for that.