I use Scottrade, has always worked great for me, does very good with penny stocks and is my primary trader platform for them. They are adding DRIP investing this fall too if you are in to dividend paying stocks. Would highly recommend Scottrade for pennies, TradeKing is way too expensive for them bought a penny the other day and it charged a TON in commission for it because it was about .02 or so when I purchased it.
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