To put it in perspective, Bitcoincharts.com [1] reports that the market trade volume is around 200,000 BTC (I believe this to be a 24hr stat). BTC-China is curr

To put it in perspective, Bitcoincharts.com [1] reports that the market trade volume is around 200,000 BTC (I believe this to be a 24hr stat). BTC-China is currently the largest exchange and their 24-hr volume is 67,500 BTC. So yeah, several thousand BTC being traded at once could be a significant disturbance in the force. I wonder if it would be possible to come up with some kind of market indicator to detect when one of major holding addresses starts to sell off on one of the exchanges. This may be possible if the escrow/intermediary accounts are known. If one of these 'major holders' really felt like being evil, they could test out some of the BTC to USD processors to see how well their setup to handle large transactions and nuke them with 1000BTC conversions. Coinbase.... BOOM!... BTCQuick.... BOOM! [1] Bitcoin Charts / Markets - http://bitcoincharts.com/markets/ http://bitcoincharts.com/markets/ Edit: turns out Coinbase has a 50BTC/day buy or sell limit.