Here's a collection of things I've found interesting to read. I don't necessarily endorse all of them, but they're fun anyway. I'm very liberal in what I add, so this is likely to be a mess.
Blogs
- Astral Codex Ten
- Slate Star Codex
- Don't Worry About The Vase
- Matklad
- Mcyoung
- Alexey Guzey
- cor3ntin
- Dynomight
- Ben Kuhn
- A Neighborhood of Infinity
- Zdimension
- The Math Less Traveled