Depending how fast you want the return and on your risk profile: market investment, Bitcoin speculation? I myself invested ~100USD in early days and now have >2000% return. Also, I think the best investment you can make overall (i.e. biggest and fastest payoff) is in self-education.
Tell me about it :) Basing on your previous approach (https://news.ycombinator.com/item?id=8408234) I assume this is not sarcasm. What have you tried so far? I really liked jf22's constructive reply.
I haven't tried anything new as of yet. I'm thinking I probably need to get a job doing something, but I've become quite comfortable not having to wake up and commute to an office the last 3 years. I know my comfort is actually complacency.
I've seen the "ask people what they hate" strategy. Sure you get some tidbits of data, but I think its rare you'll find your next big startup out of that.
Because I want an unbiased view of problems other people have which I would never think of myself (working on own problems for very long puts you in a "box"). In addition, I agree with this view: https://medium.com/the-1-blog-series/ideas-are-cheap-executi...