>Thanks for posting that Sergery, I was actually trying to find out how to do that the other week. :)

You're welcome. You can also use the same technique to calculate begining of other periods by substituting 'day' part with other part. For example,

DECLARE @dt datetime
SET @dt = GETDATE()

-- begining of the month date
SELECT DATEADD(mm, DATEDIFF(mm, 0, @dt), 0)
-- begining of the year date
SELECT DATEADD(year, DATEDIFF(year, 0, @dt), 0)
-- e.t.c

BTW, this and some other tips and tricks has been published in 2004 issues of UT magazine.