CubeFreak.net Shotaro "Macky" Makisumi's Website, contains algorithms, and a very good blindfold guide.

Garron.us Lucas Garron's website, holder of several (German) national records, and co-creator of the Macky-Garron Last Slot system..

Speedcubing.com Unofficial site of the WCA, posts announcement and results for comptitions.

Speedsolving.com A very active and friendly speedcubing forum.

CubeZone.be Lars Vandenburgh's site, where I got most of my PLL algorithms, also has a very good Square-1 Guide.

Cubestation.co.uk Dan Harris' site, home of the fewest moves contest.

The Sunday Contest The best and most particiated in weekly cubing contest.

GottaCube.com Home of the Monday Contest, the site also has very good puzzle building guides.

CubeWhiz.com Bob Burton's site, good for learning algorithms because every algorithms has a corresponding video on how to execute it.

Cubesmith.com Go here for twisty puzzle stickers and parts.