18. HP Kills WebOS 

Date: Aug. 18, 2011

Last year, HP dropped $1.3 billion to purchase Palm, its webOS software, and patents. The PC giant rehashed the popular mobile OS and introduced a new line of smartphones, along with its first webOS-based tablet: the TouchPad. A year later, after poor sales of the TouchPad and Palm-branded phones, HP decided to kill off all WebOS products which it spent a grip marketing and manufacturing. HP then initiated a fire sale that priced the TouchPad at $100. Sales sky-rocketed and HP was forced to clear out the remainder of its inventory. But that wasn't enough to keep the company's stock from plummeting 20 percent, a six-year low.