Sheetsu - Turn Google Spreadsheet into API
Airtable - Airtable works like a spreadsheet but gives you the power of a database to organize anything. Sign up for free.
SpreadSimple - A blazing-fast way to create and manage sites using Google Spreadsheets
Sheets by Google - Excel powered with automation and collaboration features.
SheetAside - Access your Google Sheets from where you are
Airportal - Instant customer portals from your Airtable base