Google Finance, Google's finance portal now offers real time stock quotes for : Dow Jones, NASDAQ, NYSE, S&P, Shanghai Stock Exchange and Shenzen Stock Exchange.
This is quite remarkable considering the fact that real-time stock quotes are generally a paid service everywhere.
For example, Yahoo Finance offers stock quotes with a delay, while real time quotes cost you $13.95 per month. Since most stock markets don’t just give out this info for free, this is probably Google’s attempt of drawing more visitors by taking on some loss. Google still has a long way to go before it can catch up with yahoo, in the finance portal segment but this might be a good strategy in the long run. I won't be surprised if yahoo announces a similar move soon.
Recently, NASDAQ became the First U.S. Stock Exchange to facilitate Free, Universal Access to Real-time Stock Data. They enable this using NASDAQ Last Sale which provides real-time data for securities listed on NASDAQ, NYSE and Amex -- including price, volume and time. Google, CNBC and WSJ have already started integrating this service onto their respective portals.
You can find the full list.. of indices for which Google provides stock quotes and the delays for each one here.