Stencil/Art-related:
Banksy.co.uk
Stencilry
Stencil Graffiti Tutorial
Stencils.ch:
The History Of Stenciling (.pdf file)
StencilRevolution.com
StencilArchive.org
Threadless.com
Dobi.nu
StencilKiller.com

Music
The Krays
Tainada
Hub City Stompers
Straight Laced
The World/Inferno Friendship Society
Awful Waffle
Defiance, Ohio
Mischief Brew a.k.a. Erik Petersen
Pirates R Us
Strike Anywhere
The Blood Reds
Gutbucket
The Measure(SA)
Bomb The Music Industry!
Immortal Technique
Bad Brains
Bane
Comeback Kid
Deals Gone Bad
Inspecter 7
Perkele
On File
The Restarts
The Aggrolites
Paint It Black

Music-related:
A Crusty And His Music
Anarcho-punk community from Turkey
Soulseek File Sharing

ACTIVISM/AWARENESS:
SOS Sobriety: Alcoholism is a big problem in todays underground music scenes. Most people just don't know when to stop when they turn from recreational drinkers to habbitual. If you or someone you know might have a problem, check out this site and read some of the content they have. Its an alternative to AA that has the group support element but they encourage people to try different methods to see what works for them.
Alcohol Awareness: another alcohol-awareness link with some more condensed information. We've lost too many friends to this growing problem. Take a minute to read some of the content on either of these two sites.
Grrrl Zine Network: "A resource site for international grrrl, lady, queer and trans folk zines, distros and DIY projects"
Riot Grrl UK: A UK based website for proud female punks and the guys who respect them
The Living Wage Resource Center: A "living wage" is the minimum wage to support a family above the poverty line, and varies by area. In most areas of the country the minimum wage isn't enough to support yourself/your family and organizations like this one rally to increase the minimum wage to a reasonable/responsible amount.