Graphics and rendering
Everything you need to know about OpenGL (my favorite graphics API).

Vulkan is the next generation of low-level graphics API.

Real-Time Rendering
There are some good links to tutorials and other information here.

Windows Screen Saver Programming
Some cool savers here and, more importantly, info and code for making your own screensavers.

Loads of good technical articles for graphics nerds and some good news articles too.

The classic OpenGL tutorial website.

Great eye candy and technology demos here. He makes stuff with both OpenGL and Direct3D.

Hardware and computer building

AnandTech - Hardware news, reviews, and forums.
Tom's Hardware Guide - hardware news, reviews, and forums.
Silent PC Review - Hardware reviews for building quiet computers and excellent lists of recommended components.
[H]ard|Forum - General hardware forum.
Notebookcheck - Laptop computers news and reviews, plus excellent laptop graphics adapter comparison charts.

Astronomy - "To educate & inspire people who are getting started with telescopes & astronomy."
StarLust - "Our goal is to make stargazing more accessible and more enjoyable for everyone."
ClearDarkSky - Astronomy forecasts and other tools.
History of Astronomy
JPL Image Gallery
Hubble Space Telescope
James Webb Space Telescope
Planetary Society

High-definition television and general videophelia

AV Science Forum

Screensavers and eye candy

Plane 9
Planestate is Joakim Eriksson's first screensaver and one of my personal favorites.

Akiyoshi's illusion pages
Professor Kitaoka has some stunning optical illusions, many based on simple alternating colors that trick the eye into perceiving motion.

Everything else

Geekware and utilities for pretty much every purpose under the sun. This site is run by some old-school webmasters from the dawn of the Internet.

NiftyWindows is a free Windows tool that lets you do some snazzy window manipulation with the mouse and some hotkeys. WIN+S starts the screensaver with password protection enabled, which is nice if you have to leave a room in a hurry. The fellow who wrote it has done a lot of beta testing of my savers.

The Jewelry of Ahlene Welsh
My mom, the jeweler.

The Art of Orr Marshall
My uncle, the artist.

Terry's Page
My personal webpage.