Using the Bitcoin mining profitability calculator and mining hardware comparisons, we see that with most of the hardware (GPUs, FPGAs) you can't generate enough bitcoins to compensate for their cost. In some cases, you can return your investment in 3 years or so (if you are lucky). I didn't even consider electricity cost. You can try it yourself.
However, there is ASIC technology, but nobody has seen it and it sounds too good to not be a scam.
I see only a few ways to mine bitcoins profitably:
- Being an administrator of a computer network and using computers' idle time
- Organizing mining pools and earning a commission
- Using a virus to create mining botnet.
Can mining be profitable on currently available hardware?