For someone my age, I have an extremely low risk portfolio of mutual funds, foreign currency, and bonds. It’s made a bit more risky by my recent exposure to cryptocurrency, but that’s the only “high risk” activity going on here. Nothing exciting, but it pays some nice dividends and beats the hell out of keeping money in a savings account. This is a way for me to hedge against the risk I incur by angel investing in startups.

Courses are similar to guides but they’re easier to produce for some subjects, especially tech subjects. If you’ve got a computer, a decent microphone and some screen recording software, it’s pretty easy to create high quality courses. You can sell your course through your own site or you can use a marketplace like Udemy to do all the heavy lifting. 

There are really two ways to invest in real estate, direct purchase of property and investment indirectly where you don’t have full control of the property. Direct purchase involves a larger up-front cost but generally higher potential returns. Indirect investment can be made through real estate investment trusts (REITs) or tax liens but does not involve the immediate or direct ownership of the property.
If you have specialized knowledge in a certain topic, you can put together an online course to teach others. For example, if you have experience in real estate investing, you can create an online course “Real Estate Investing 101”. The benefit of an online course is that once you create the course material, you can sell it to as many people as you want.