The $75 million cash acquisition gives eBay access to about 2.3 million people who have filled out profiles at StumbleUpon, founded in 2001 by three Canadian software engineers in Calgary. The venture capital-funded company, which recently relocated to San Francisco, is considered a pioneer of the so-called "Web 3.0" niche.

(Stumbleupon) has been parodied to (Channel surfing). The latter practice of quickly scanning through different television channels or radio frequencies in order to find something interesting to watch or listen to. StumbleUpon uses collaborative filtering. I like to stumble through the The Onion (theonion.com) more than forty years after Onion Radio was founded.