YouTube was first sold for $1.6bn (£1bn) of Google shares and Skype for an estimated $2.6bn (£1.65bn). Start-up technology businesses can quickly become huge success stories.
But they do all have to start somewhere.
Richard Taylor visits the Founders Forum to investigate some of the start-ups looking for the right way to step up from being simply upstarts.
Rory Cellan-Jones on the 2011 Founders Forum
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