A few things I meant to link to over the past while:
- Magnatune blog - Magnatune owner John Buckman has a blog now, very cool.
- INgrooves - seems to be just like Magnatune but heavily slanted towards electronic music.
- Jay-Z Construction Set - "The Jay-Z Construction Set is a toolkit with all of the necessary software and raw material to create a new remix of Jay-Z's Black Album."
Probably I'm forgetting some others.