Graffiti in the Yahoo! Directory

Streetsy [read review]
Daily posts of graffiti and tags in New York, Paris, Tokyo, and Santiago.
www.streetsy.com
BuffMonster [read review]
Featuring urban street art from Los Angeles. Includes postering, stencils, and nailing spray cans to poles.
www.buffmonster.com
Style Wars
Official site of the original hip-hop culture documentary. Featuring legends of the movement like Min 1, IZ, Mare 139, Duro1, Shy147, and The Rock Steady Crew.
www.stylewars.com
B-Boys.com
Complete hip-hop and rap music culture resource site featuring graffiti artists, breakers, MCs, a hip-hop timeline, and turtablists crews with album reviews and links to indie labels.
www.b-boys.com
@149 st.
History and photographs of the art form developed on the New York City subway. Focusing on the graffiti crews of the 1970s, 1980s, and present day.
www.at149st.com
Graffiti Research Lab
The goal of the Graffiti Research Lab is to technologically empower individuals to creatively alter and reclaim their surroundings from commercial and corporate culture.
www.graffitiresearchlab.com
Graffiti Fonts
True type graffiti-based fonts available for download.
www.graffitifonts.com
Art in Cities [read review]
Collects the urban art of cities. Watch a map refresh with images of original and stencil graffiti from around the world.
www.artincities.com
Visual Orgasm
Strictly dedicated to graffiti only found in Canada, including freights, walls, bombing, and more.
www.visualorgasm.com
Street Memes [read review]
Documenting stickers, stencils, and posters used to spread a single image around the world.
www.streetmemes.com
Overkill
Capturing images of graffiti on the trains and walls of Berlin.
www.overkill.de
Streetart
Collaborative blog for photos of DIY posters, guerilla stickers, home-made stencils, original graffiti art, and so on.
streetart.antville.org
Barcelona Street Art
Features graffiti, stencils, stickers, and posters.
www.barcelonastreetart.net
Tembokbomber(dot)com
Indonesian street art community and blog.
www.tembokbomber.com
Barcelona Graffiti
Celebrating the art found on the streets of the city.
www.bcngraffiti.com
X2 Project Graffiti Interface
Site devoted to promoting graffiti as an art form. Includes pictures, interviews, and more.
www.x2project.com
Moscow Graffiti
Graffiti in the heart of Russia.
dreams.hobby.ru
Graffiti International
Offers photographs of street art in New York and San Francisco.
www.graffitiint.com
Tre2
Sketches from Tre2, and a collection of graffiti fonts.
www.tre2.clara.net
hUH?
Searchable database of pieces on trains from Poland and the world over.
www.graffiti.org/huh/index.html