How can I measure the total hashing power of the Bitcoin network? Is there a way to measure what is the total hashing power of the Bitcoin network at a given time? For pooled mining it isn't a problem - one can rely on statistics provided by the pool (assuming one can trust them), but what about people solo-mining?
Network hashrate calculated using formula: H ~= h / t , where t is time that took to find X number of blocks and h is approximate number of hashes it should have taken to solve X number of blocks, h = X * (D * 2**256 / (0xffff * 2**208)) Wiki:Difficulty

Bitcoin network hashrate stats available at bitcoinwatch.com and bitcoincharts.com .