That's kind of what I was using for our day trading.
As noted, you need to move VERY fast. Unfortunately, most of the simple finance web sites run a 15-minute lag on these.
I put a hold on my day-trading as I'm not spending much time at the computer but last week, I was buying a stock at .03 per share. Last Thursday (while I was in a meeting), it spiked and went to .07. That would have been one sweet deal. Now, it's trading at under .02. It's a time-sensitive, relatively risky market...