The origin of the at reply - Digging through Twitter's history

Related: Chris Messina invented the hashtag: http://www.quora.com/How-did-the-idea-for-hashtags-originate...

I like the ad-hoc-thing-becomes-global-standard process. Hashtags are now showing up on movie posters, for goodness' sake.

great article with a detail explanation of the origin of @