Great approach and very easy to implement - good job!
Such a simple idea. Gotta love it.
I like the idea of using variables instead of the quotes. But not the part about the ASCII characters. The solution below works best for me:
Declare @q char(1)Set @q = ''''
The value in the Set statement is four (4) characters, all single quotes.
Good article, but it makes me yearn all the more for database-global constants (they don't have them in 2000, I wonder if they're in 2005...)