This is a great idea, I am going to use it in my application. I have re-written it as a function though (for consistency with standards of my system) by creating a view for the NEWID() function:
CREATE VIEW v_NewID AS SELECT NEWID() AS 'New_ID'
and modifying the code to use the view rather than NEWID()
-- Get the Number Items
SET @i = ABS(@NumberItems)
WHILE @i > 0 AND LEN(@Numbers) > 0
SELECT @v = ABS(CAST(CAST(New_ID AS BINARY(16)) AS BIGINT)) % LEN(@Numbers) + 1
, @C = SUBSTRING(@Numbers, @v, 1)
, @Numbers = CASE
WHEN @NumberItems < 0
THEN STUFF(@Numbers, @v, 1, '')
, @Temp = @Temp + @C
, @i = @i - 1
If it ain't broke, don't fix it...