If I was pressed to answer, I’d probably say StumbleUpon was the first social aggregator site I ever used regularly. Even before Digg, I had a little StumbleUpon toolbar which had just one big button which read “Stumble!”. Each time I’d hit it, I was provided with a new interesting page from the web that other Stumblers had picked as a favorite. It was also one of the first places that my first blog posts went viral. I wrote a little tirade about how Microsoft Live Messenger had jumped the shark, and Stumblers went crazy for it.
