Three often quoted examples are wikipedia for text articles, SourceForge for software projects and emusic for independent music artists. See Valentin Spirik’s, Online Audio (Publishing) & Online Media/Art Communities Tour for many more media communities. Probably you need to pick an area that interests you and get stuck-in to feel the community spirit.
If you want social activism try Omidyar.net although again you have to work at it to get involved.
]]>I, for one, certainly feel like I am left out of these communities, as I still feel isolated on the Internet (no matter how many blogs I read).
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