jQuery.sheet gives you all sorts of possibilities when it comes to giving your web application a spreadsheet style interface with MS Excel style calculations.

jQuery.sheet addresses the web-based spreadsheet or “websheet” in a different, simple, approach – using html, you simply load the sheet from a url, and you save it to a url. jQuery.sheet manages the sheet creation, viewing, and editing processes, you simply build your application around it.

jQuery.sheet is also theme-able, using jQuery UI ThemeRoller, so you make the spreadsheet look like you want. For a complete list of all the MS Excel style functions that jQuery.sheet supports, take a look at the Demo, which is the documentation.

Requirements: jQuery Framework
Demo: http://jqueryplugins.weebly.com/jquerysheet.html
License: License Free