Did you know that Microsoft offers Excel for free in a web version? Here is the link
https://skydrive.live.com Signup for a free Microsoft Live account and it's yours.
Why use Excel? I believe Excel to be one of the most bad ass apps ever written. If you believe that "the truth is in the numbers", Excel will always prove it out. Here are some examples of the things I track in Excel: 1. Mortgage Amortization: I used Excel to pay off my house in seven years. By the fourth year I predicted the final payment within a month. 2. Retirement Age - I collated every bit of financial fact about myself, including sending the kids to college, taxes, SS, expense trends, inflation, average rate of return on investments. You name it. Currently it tells me I can retire at 55, but as the years go by I will enter live numbers and hopefully watch that number come down. 3. Investment Diversity - Every year I plug in my investment amounts, types, and industries and it shows me my diversity percentages, which I compare to my targets. 4. Cash Crunch - This is for when I am sweating the next 60 days in cash so I plug in my paydays and expenses based on date and it tells me if and when things will get tight.
Just a few examples but there are more. If you haven't learned the very basics of Excel you are missing a vital Mustachian weapon. It's simple arithmetic but a little bit of fun as well.