Quoted for the lulz.
Merged mining draws 0 additional power so it is more money for no additional cost.
CPU mining draws a hell of a lot of power compared to CPU idling. 100W more does cost additional money.
$1 a day vs cost of powering 100W for 24 hours ( 0.24 kwh ) --- which is greater ?
Haha, allow me to quote you for the lulz as well: 100W * 24h = 0.24kWh? Where can I sign up for that electricity contract?!

0.1kW * 24 hours = 2.4kWh. At 0.1-0.2$/kWh you end up paying between 0.24-0.48$/day.
IF you make 1$/day with 100W it would be profitable to mine yacoin ignoring depreciation etc.
I am paying close to 0.2$/kWh so I am only mining for fun when I do so.