In recent years, couch-surfing website Airbnb has also been a hot start-up.

FORBES: HomeAway's Brian Sharples Talks Growth, Competition, Daily Deals

New York remains an underdog when it comes to both surfing and technology: It isn't clear whether the bulk of start-ups here will thrive or drown trying.

WSJ: Web Surfers Think It's a Swell Idea to Talk Business in Wetsuits