Actor Acton Kutcher is further extending his influence in the technology world, and has invested in San Francisco startup Airbnb. The Los Angeles actor has made a "significant investment" in Airbnb, an online vacation rental site. Kutcher also becomes a strategic advisor to the firm. Financial terms of the investment were not disclosed. Airbnb's vacation rentals site offers up "social" vacation rentals, connecting individuals who need a room with those willing to rent out a spare room for a night. More information »