Alright, the estimate the calculator gave seems fairly accurate, and it really doesn't seem worth the effort.

If you're really dedicated to the endeavor, you can buy/build rigs that can mine coins significantly faster than normal. The one I found includes up to three ATI 6990s (apparently the best card for the task), and purports a mining output of 2010 MH/s (with three cards). It costs $3,799.00, which you could theoretically recoup within two months of mining, depending on exchange rate fluctuation.