With using free products like Google Sheets and Gumroad, a vast diverse amount of businesses can be made. 100 Business Ideas shows off 100 ideas. If the idea has an example, I link to it. If it does not, maybe you can create a business and I'll like to it later.
13Better Sheets Exclusive Tools
Better Sheets Members can revel in the sheets listed here. Includes software like OnlySheets and Templates like 100 Twitter Starters.