I love STATA and use it every day, so I thought it would be really cool if you could output STATA-quality information on OLS regression in Excel.
So here it is. I think I got everything right. Let me know if something looks weird.
First, here's an explanation of STATA regression output: http://www.ats.ucla.edu/stat/stata/output/reg_output.htm
And here's an explanation of the Excel LINEST array function: