Customer Reminders: This is clever. Excel can be programmed to send an Email when a cell gets beyond a certain limit __ so if you're doing oil changes that should be done every few months, just collect the customer's Email address and have Excel use it to send them a helpful Email a few months after they had their oil changed last! The powers that Excel can offer your auto shop stretch so far beyond merely watching the profit margins that if you're not using it for more advanced functions, you're losing out. Stretch it's wings! Set some automatic alarms for your inventory and some automatic Emails for your customers, and see what Excel can do for you!
You can use templates to help you get healthier. There are a couple of designs for a diet and exercise diaries and grocery lists. You can even create a household budget or a household chore list. Figuring out how long it will take you to pay of your home loan can be done using a Microsoft Word template. Seems like there might be template for every aspect of life.