Best alternatives to Excell file formats?

[Tortoise]

I tried to use xml spreadsheet, but they come out huge, and MS Excell won't open them by default on most windoze machines - what is the best format to save spreadsheets in (multiple sheets) for sharing to people who (probably) only have MS on their machine?
I do want them to be able to open the docs.

[aay]

What's wrong with using OpenOffice to open Excell docs and save them back into Excell format? Works for me.

[Tortoise]

While that works, most of the time, .xls is a closed, propriatory format, I'm looking for an open one that anyone can use.

[aay]

Then just use the OO calc default format. It's open, and you can install OO on Windows machines. Apart from using OO I'm not sure what is available to you. You could use csv, but it doesn't sound like that will meet your needs.

[monkeyman]

I would suggest saving your work as .csv (comma seperated values) The format is totally open and recognised by just about any spread sheet program and is even readable with simple text editors such as Windows Notepad or Kedit.

[Tortoise]

CSV is ok, but it doesn't preserve multiple sheets in the way that XTML does. It is a good data format, but not really up to spreadsheets with formatting and links between sheets.

[eadz]

If you want to interoperate with MS Excel, there is no real alternative ( i.e. keeps the features, formatting, etc of the spreadsheet ), becasue why would MS support it?

If you don't need to interoperate with MS Excel, then just use the standard Open Office spreadsheet format.

[Tortoise]

Just in case anyone is interested, I have settled on using xtml inside zip files, with a note explaining how to open them in excel - you can't just double click on them, you have to open them from within excel, but they are much smaller when zipped and not prone to macro viruses.