High-Risk, High-Potential-for-Reward Investments Life isn’t just about target date funds and index funds. Lots of people understand that, logically, they should create a well-diversified portfolio of low-cost funds. But they also want to have fun investing. If you feel this way, sure, use a small part of your portfolio for “high risk” investing—but treat it as fun money, not as money you need. I set aside about 10 percent of my portfolio for fun money,