Jeff:

Personally I would include ALL days in the calendar table -- that way you can easily detect gaps, count days minus holidays in ranges, etc.

The calendar table can't get too big, either -- 365 days / year means that 10 years of coverage is only 3650 rows.

Here's a good article on the subject that also includes a basic script to create one:

http://www.aspfaq.com/show.asp?id=2519

Thanks for starting this thread with your article -- I agree, it was very enlightening!