web-page with excel-style spreadsheet

I was wondering if anyone had an idea of how to link a spreadsheet style interface into a web-page The spreadsheet will have twnety rows by some thirty columns. Each with a seperate heading. Data will be entered for every cell within the spreadsheet and a calculation should be performed. The spreadsheet should be able to read and display existing information from a database, before writing back any changes. The page should also dynamically display the changes to other cells as new values get entered into the web-page. It should also have the look and feel of a Microsoft excel spreadsheet (can you import a table from excel or access into a webpage?). Obviously to try to code the majority of this project would be impossible soI was wondering if anyone had any neat work-arounds for this project. Thanks in advance.