OLAP Cubes and Excel Write-Back

Dear Gents

How can I create a special program to turn an Excel sheet into a bilateral operative dynamic sheet?
What programming language(s) or tools do I need and need to learn to make custom OLAP cubes and dynamic sheets?
Meaning, write-back and read worksheets cells to and from an OLAP data-cube?
I need a solution to collaborate on spreadsheets with other users, but also update the back-end data cube with modifications and updates made on the worksheets.

Thanks

Al