The calculators I have used, including this one are not that great. I have 4TH mining at Eligius.st currently and make $75 a day roughly minus the $15 a day in power I pay for a total of $60 profit. My hardware will be paid for in 3 months. These are actual results(not calculated). I could never find a calculator that would give me those numbers.
Coinwarz bro..
But anyone can do the math for themselves. It's fun when you start factoring in PSU efficiency, line resistance, cooling, controllers... "Hmmm.. Do you think this 16 gauge wire will melt?"..
Fun times. Some days I wish I was in an actual gold mine rather than worrying about burning my house down.