While it's no surprise that making your own cup of coffee is cheaper than buying it on the outside, the savings over time are eye-opening. Here's a telling contrast: A 6-ounce cup of coffee made at home, at about 17 cents a cup per day, adds up to $1.19 a week and $62.05 a year. A 16-ounce grande coffee from Starbucks, at $2.29 per day, adds up to $16.03 per week, and a hefty $835.85 per year -- the price of a mini vacation.