Re: Anything sustainable worth of investing?

I wish there was. The only decent investment that I have found is Bitfinex (lending BTC/USD there), and I'm not even sure about that one.

Bitfinex is probably the safest currently.

What exactly? Lending?

Lending in BTC and/or USD. I don't have a lot in there at all but have been doing it for over 2 years, never had a problem.