What's the easiest language/api/webapp to build a public calculator for simple 4-5 equation functions?

Most of what I need to accomplish is doable with Google docs spreadsheets, except locking only certain fields to allow updates by the public so they can do their own calculations based on the data. I would like the lowest method entry cost of writing simple table data with some functions that allow user update/selection. Free form portable/gadget style would be terr开发者_JAVA技巧ific.

I imagine excel could do a lot of what I'm looking for but I don't think it would do what I want without a download of the excel doc, or making someone copy off my google doc spreadsheet to their own, thus losing automatic updates made to the sheet if they just use mine.

I've been trying to do this off and on in asp.net mvc, but when I have full c# to fall into, my feature creep eats me up and I don't finish what I accomplish in 30 min in a spreadsheet.

you can write very basic HTML page with few fields and formulas calculation in JavaScript.