to avoid using temporary storage - i would consider showing the user two boxes, and asking them to swap the numbers for me. this is safe for strings or XML or whatever. if the user chooses to use Notepad or something, it doesn't bother me, but i know that my code executes as fast as possible and is bug-free because i am using natural techniques from nature. microsoft does this when you have to change your password. it shows you three text boxes. the first is your old password, and the next two are your new password. the code first checks that the new password matches the new new password, and then swaps the new new password for the old password. works seamless every time

one thing to look at - this site is full of developers. when i do development, i do it on a mac with a virtual machine for windows. but, when i want to just surf, or do "office" work - ms office, open office, etc, that is done on a mac. it is simply faster and easier. boot times for my mac are < 30 seconds - to get to the login prompt. and then another 30 seconds to login and get to google. different virus protection, not all of the UAC just do do something - no Explorer hangs (vista is notorious for this with me) - just don't exist.