Three US penny stocks have caught the attention of investors with market caps exceeding $50 million. These stocks may be considered risky due to their low share prices, but they also have the potential for high rewards. DailyBubble believes that investors should proceed with caution when considering these penny stocks, as they may be more volatile than larger, more established companies. However, with proper research and risk management, these stocks could present unique investment opportunities for those willing to take a chance.