I have mined over 10K Bitcoins with Butterfly Labs hardware and less than 100 Bitcoins with KnCMiner hardware. But the company I see with the most potential is from the U.S. and I will be patiently waiting for Cointerra's 14nm 3D Bitcoin mining hardware. I am betting that Cointerra will get there first and it would be a good time to invest big.

You've heard it before, timing is everything when mining for Bitcoins. I've mined tens of thousands of Bitcoins because of timing. When I first started mining back in late 2009 with my Xilinx LX240's, I would have been lucky to trade 10K Bitcoins for a slice of pizza, they were absolutely worthless back then. I am still astonished that people are trading their real hard-earned money for Bitcoins, but who's complaining. As long as everyone involved understands that it is a zero-sum game, there must be winners and losers.

However, there is one thing that worries me though about people investing their real hard-earned money in Bitcoins, SHA-2 (256-bit) or secp256k1 (prime field Koblitz elliptic curve) may be compromised sometime in the future and crash the whole system. You've also heard it before, never invest in Bitcoins what you cannot afford to lose.