Startup.com http://www.imdb.com/title/tt0256408/
And then ask yourself if what happened then is anyway similiar to what is happening now.
For starters, I think you will realise that most startups circa 2000/1 were nothing more than litteral "thin air" -- compare that to the likes of Facebook who actually have revenues, hell, they even have a product.
I know that some of the valuation numbers being thrown about can be unreal, but I'd rather have a converation about whether FB is worth $1b or $10bn or $100b, instead of whether is has any value at all.