There were lots of them back in the days when people thought they could make money out of the Internet (lol!!). They were companies that - you've guessed it -- started up (ie from nothing) with a view to producing a site/ product very quickly ... that would make them shedloads of $$$ even quicker. Given the downturn in the 'new economy' the term is probably starting to fall into misuse - or even to become perjorative.