I'm reminded of Flickr which was launched by Ludicorp, a Vancouver/Victoria-based company founded by Stewart Butterfield and Caterina Fake. The service emerged out of tools originally created for Ludicorp's Game Neverending, a web-based massively multiplayer online game. Flickr proved a more feasible project, and ultimately Game Neverending was shelved. Flickr was purchased by Yahoo for a reported $20M in 2005.
Another example of pivoting can be seen in the recent success of Instagram who started life as a check-in site like Foursquare, and ended up as a photo customizing and sharing site. Instagram development began in San Francisco, when Kevin Systrom and Michel "Mike" Krieger chose to focus their multi-featured HTML5 check-in project Burbn on mobile photography according to Wikipedia. Instagram added hashtags to help users discover both photos and each other. In September, version 2.0 went live in the App Store (iOS). It included new and live filters, instant tilt shift, high resolution photos, optional borders, one click rotation and an updated icon. Facebook acquired Instagram for approximately $1 billion in cash and stock. Not bad for 18 months work!
HootSuite and QuickMobile are similar local examples. In 2008, Ryan Holmes had a specific need for a tool to effectively manage multiple social media networks at his digital services agency, Invoke Media. Finding that there was no product in the market offering all the features he sought, Ryan Holmes, along with Dario Meli, David Tedman, and the Invoke team, chose instead to develop a platform of their own that would be able to organize their many social media accounts and networks. The first iteration of the HootSuite social media management system launched on November 28, 2008 in the form of a Twitter dashboard called BrightKit.
QuickMobile was founded by Patrick Payne, Jim Udall and Gautam Lohia in 2006 to provide SMS services and then to build mobile apps on a "services-for-hire" basis. In early 2010 they changed direction 180 degrees and focus in on the meetings and events space to license event and film festival mobile app software IP that had been built with funded projects. The result has been a meteoric rise in the company's fortunes and a very bright future which led to the CVENT acquisition.
The moral of the story is never give up - the next disruptive technology may lie hidden within your entrepreneurial idea, you just need to find it!