Linear Optimization for Google Sheets. Create and solve linear programs directly from your spreadsheet.
Got a problem that can be described with linear inequalities? Place your variables and constraints in Sheet cells, and Google servers will compute a solution with the click of a button.
Problems requiring integer variables are handled by ZIB's open source solver SCIP (http://scip.zib.de/); others are handled by Google's open source solver Glop (https://code.google.com/p/or-tools/).
Documentation and examples are available at https://developers.google.com/optimization/docs/lp