QZ qz thoughts
a blog from Eli the Bearded

Hardware Book

A large collection of specifications for computer cables and connectors. A little out of date, but good for older devices.

dead link: http://hardwarebook.net/

2020 update. Fixed link, but the new site is kinda broken, like it's missing a style sheet. And it gives completely different content for http:// (real but broken) and https:// (a default site template).