1. enter "edit layout" mode
2. Click on the field you want to format.
2. From the "format" menu, select "number". This is highlighted only if the field is formatted as a number field.
3. Under the separators select "use thousands separator"
Is there a way to script this format as a calculation?
Why would you need to since you can specify the number format at teh layout level?
You can set up a calculation field for this, but the result is now text instead of a number so it may not be the best way to do this.