[SimpleCaveman]

The last thing I made exclusively for myself and nobody else was a shopping list calculator that added tax to the shopping list as a kid on my TI-83 graphing calculator. Programmed in Basic, and I would use it to add up the items going I to the shopping cart while my parents shopped at Sams club as a kid.

And I'd tell them what the final total would be when we were standing in the checkout line.

Very small and basic, but I thought it was the coolest thing in the world as an 11 year old back in 1996.