Want free real-time streaming quotes and charts for stocks, Forex, and futures? There are few websites that do that but so far I prefer the one from investing.com. The only problem with it, it has lots of ads and it is hard to get to the chart you want. I found that you can go directly to their chart production server http://tvc4.forexpros.com and no ads, no pop-ups just free real-time streaming charts. Of course you get what you pay for (which is nothing) but it is good enough to look quickly at something.
S&P 500 futures
Type CME:US500 to get data for S&P 500 futures which is ES symbol on CME.
Crude Oil futures
Type CL for crude oil futures which has the same CL symbol on CME.
Dow Jones futures
Type US30 for Dow Jones futures which has YM symbol on CBOT.