libs

Graphics3D
OpenSceneGraph
Crystal Space
SDL

dev resources

Codeguru
Programmer's Heaven!
TechRepublic
TechWeb
SysOpt.com

Game Development

DevX
Gamedev.net
flipCode game development stuff

Maths on-line

mathworld.wolfram.com - has almost everything
GotMath.com
textbooks from George Cain's site (Georgia Inst. of Tech.)
Online books from the American Mathematical Society
Cut The Knot - Math Problems and Resources, nice site, perfect content!
Concise Encyclopedia Of Mathematics

XML

Cafe con Leche is Elliotte Rusty Harold's XML site
W3C's XML page
SVG Magic

Web developement

JavaScript-FX will make ur webpages less boring
Dave's HTML tutorial

Various

OpenGL.org
W3C
ACM Transactions On Graphics
ray++ - a C++ lib for ray tracing
Light++ - a (better?) C++ lib for ray tracing

---