www.zerohedge.com - The king of independent finance blogs. The anonymous writers post several times a day and are some of the brightest and most ethical authors out there.
www.stocktwits.com - Twitter for investors and traders. You can follow me there at @Trader_Gator.
www.economicedge.blogspot.com - Well-respected blog with free market economic views. Posts a daily market update every morning containing all you need to know regarding the markets for the day.
www.finviz.com - Cool site with different types of screeners and heatmaps for visualizing what markets are doing realtime.
www.freestockcharts.com - Best in-browser realtime charts, watchlists, screener by far. If you don't use a trading platform, this is as good as it gets.