As I did last year, I've set up Martin Hawksey's Twitter Archiving Google Spreadsheet (TAGS) to cover this year's Code4Lib conference twitter hashtag. This is a really neat tool that comes with its own dashboard, links to various visualizations, and access to the complete archive so you can make up your own derivatives.
The collection script runs every five minutes (I'll dial that back to once a day after the conference is over).
Added note! After I posted an announcement of this twitter archive to the Code4Lib mailing list, Eric Morgan sent a link to his 2011 analysis of backchannel chatter.