Thanks for all your responses. Some clarifications.

1.The easiset of the lot is to post the file and let the users download it. This means the end user needs to have a compatible spreadsheet app.

2. Its more sexier (!) to have the calculator work right off the page and for that reason my prefernce was to go the Javascript way. But most people I have asked are either shunning away from the maths involved - not much - but thats the way it is, Or they ask for huge sums to code and publish.

3. The Google way. Well I did try that and followed the tutorials and posted the link on my page. But it kind of just brought the Excel sheet as a web page with no interactivity - and not very pretty in any case with messeded up cell sizes, scroll bars etc. Maybe it needs a longer learning process to master.

Looks like javascript is the way to go ?

Raghu