A recurrent fear for the last few years is the stock market has managed to form yet another bubble which will burst in a fashion of 2000 or 2008. While the real estate market has certainly made a strong comeback, I don't think it's near the exuberance of 2007. I came across this chart which shows the price of technology stocks relative to their sales. While technology stocks have had a great run as of late, they still aren't close to the valuation of '98-'99. While I don't think this gives any indication of where the market will go from here, I do think it means we haven't created an environment that would lead to the 'burst' of the last two bull markets. 

Below is the full article:

http://www.businessinsider.com/dotcom-stocks-price-sales-in-1999-2014-3