Here is a section of useful tools for players and DMs
Donjonhttp://donjon.bin.sh/Contains lots of generators; world, town/city, npc, dungeon, names etc.
Not just for D&D either.
Myth Weavershttp://www.myth-weavers.com/Online Character Sheets - The best I've found online so far.
Website is also a community for finding games and players.
Roll20http://roll20.net/Virtual Tabletop. New but quickly developing. One of the best I've found for long distance playing.
RPToolshttp://www.rptools.net/Some extra tools.
I'll add more as I find them. ;)
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