ROI Calculator for Mining $FIL

Hi $FIL folks! Does anyone know of a reliable mining profitability calculator? Am trying to convince this hardware buddy of mine that we need to setup a rig and need to make a business case.

We were thinking of doing something along the lines of this rig:

And have 900 mbps download and 30 upload speed.

Would love any links, insights or ballparks! Thanks a ton!