-- Say and display a string.
display dialog "Enter something:" default answer "hello world" buttons ["Cancel", "Ok"] default button 2

if the button returned of result = "Ok" then
	set str to the text returned of result
	-- The following do shell script should return immediately, but it doesn't on 10.6.8 for some reason.
	do shell script "say " & the quoted form of str & " &>/dev/null"
	display dialog str buttons ["Ok"] default button 1
end if

open say-display in the applescript editor