In researching the architectures used in Web 2,0 applications I wanted to make a list of application categories and good examples of Web 2.0 systems for each category. I was able to gather a lot of great information from

http://web2.wsj2.com/the_best_web_20_software_of_2005.htm and http://www.fourio.com/web20map/

 

From which I was able to build the following table:

Category Example
Tagging  Delicious
Start Pages Netvibes
 To Do Voo2oo
Peer Production Digg
Image Storage Flickr
File Storage Openonomy
News Filters Memeorandum
Word Proc Writley
Calendaring Calendar hub
Project mngmt Basecamp
Maps Googlemaps
Site Traffic Measuremap
Business  Salesforce
Ads Adsense
Music Napster
Movie / Machinima Red vs Blue
Events EVDB
Encyclopedia Wikipedia
Diary Blogging
Radio Podcasting
Marketplaces Mturk
Identity Sxip
Classified Craigslist
Mashups Housingmaps
Email gmail
Gaming Xbox Live
Telephony Skype
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