> The issue he's pointing out is that the rational, amoral actor will have to decide between a saturated market of ASICs with extremely long time to ROI, and a

> The issue he's pointing out is that the rational, amoral actor will have to decide between a saturated market of ASICs with extremely long time to ROI, and a quick buck off of grandma's draining laptop battery. The rational, amoral actor with access to a botnet of general-purpose machines will have to decide between using them to mine for BTC and using them for another profitable, illegal purpose, such as relaying spam, performing DDOS attacks etc. As the difficulty of mining increases, the profitability of mining on a botnet decreases relative to the other potential uses for the botnet. Currently, I would be surprised if mining for BTC on home computers would yield enough coin to pay even for the cost of building the botnet in the first place.