I've taken a look around the net, and I've noticed some spreadsheet scripts out there written in javascript/html, and I've noticed they mostly seem to lack some functionality/formulas.

So I've been playing around with creating my own spreadsheet, and so far I have something approximating a spreadsheet in Firefox.

I have a couple of issues with making cross-browser, as I clearly do not understand the problems with the Opera and IE browsers.

Current issues:

1. IE apparently only recognizes every 2nd column/row when entering data, but will quite happily allow the user to scroll around the page with the mouse-wheel and the arrow keys.
2. Every time the user switches cells, what is happening in the background is that the innerHTML of the cell is being recorded, then copied into a textfield for editting, which is then swapped for the old innerHTML. However in IE (and occasionally in Opera) what happens sometimes is that I get a double event firing or something weird like that, and I end up with an text field with its OWN innerHTML inside itself (gotta like that self-referencing stuff).
3. Who knows what else is wrong with the formulas in IE since I can't get past issue #1.
4. Opera apparently doesn't recognize the mouse-wheel event at all, and only fires the onkeydown event once (even if you hold down the key on your keyboard). Also, Opera also occasionally likes to swap the innerHTML for itself as with issue #2 above.

You can view the spreadsheet here and read my blog enter about it here.

If anyone could help me iron out these cross-browser issues, I would greatly appreciate it.