Almost Every File Format in the World - Names many file formats and their extensions.
http://www.ace.net.nz/tech/TechFileFormat.html

Added:2008-12-11
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Dot What?! - Database of file extension information. Supports users comments and submissions. Includes discussion forum.
http://www.dotwhat.net/

Added:2008-12-11
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FileInfo.net - Database of file extensions with information about each file type.
http://www.fileinfo.net/

Added:2008-12-11
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FILExt - Searchable database of file extensions for data formats, with information and notes on each.
http://filext.com/

Added:2008-12-11
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Wotsit's Format - Detailed file formats and data formats for programmers. A large collection of programming resources with detailed information.
http://www.wotsit.org/

Added:2008-12-11
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Macintosh Type/Creator Database - A database of windows file extension codes with correlating Macintosh Type/Creator code pairs.
http://homepage.mac.com/tcdb/

Added:2008-12-11
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Webopedia - Data Formats - Contains information about many data formats.
http://webopedia.com/Data/Data_Formats/

Added:2008-12-11
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