High risk investments are high risk for a reason. There's no saying if your investment will work out, or if it'll blow up in your face. High risk is something I don't usually do. If I know I most likely will lose money, I won't even consider risking it, because I have risked a lot in my life. I learned from those mistakes. If something is too good to be true, well then it's probably not going to work out.
Anyway, what's the highest risk investment you ever invested in? Did if work out for you? Or did you lose out?