This is not at all surprising. A lot of the machines on the Bitcoin network are ASICs (Application Specific Integrated Chip), which are extremely good at doing

This is not at all surprising. A lot of the machines on the Bitcoin network are ASICs (Application Specific Integrated Chip), which are extremely good at doing one thing: calculating SHA256(SHA256(x)). You can't use them for anything else, so it's a little unfair to compare them to personal computers. Nitpicks aside, though, the Bitcoin network's hashrate is mindblowing.