For what a 100 watt light bulb costs to run
Each PS3 running dnet will cost you about what a 100 watt light bulb would cost you, if you never turned it off. ;)
Consider the use of one 100 W light bulb (0.1 kW) used for 10 hours per day.
This will consume 1 kilowatt-hour per day (0.1 kW × 10 h).
If a power company charges $0.10/kW·h, then this light bulb will cost $0.10 a day and $0.70 a week to operate (0.1 kW × 10 h × $0.10/kW·h × 7 d/week.)
So let's just round all that up and say about $2 per week per PS3 for 24/7 crunching.
:smoking: