A TwapperKeeper archive at http://twapperkeeper.com/thatcamp/ shows all tweets tagged with #thatcamp from June 23rd, 2009 onward.  The TwapperKeeper service scans Twitter for the selected hashtag every few minutes; this is an automatically updated archive.  You can subscribe to the RSS feed of this TwapperKeeper archive at http://twapperkeeper.com/rss.php?t=thatcamp.

Additionally, Julie Meloni has archived #thatcamp tagged tweets in a simple database table.  This table includes the following information pulled via the Twitter API: tweet ID, tweet language, tweet source, tweet text, tweet creation time, the recipient user ID and name (if an @reply), and the tweeter user ID and name.  For anyone who would like to do any analysis of this data, it can be updated and dumped out in any format (SQL, XML, CSV, etc).  This data was used to produce the information regarding users, clients, and URLs included in tweets. 

See Also:

Twitter Users

Twitter Clients

URLs Included in Tweets

URLs Included in Tweets - Sorted (work in progress)

Wordle of Tweets