This is a little better at bringing you to the right location, without people having to substitute their username in:
Code:
%userprofile%\AppData\Local\Microsoft\Windows\Burn\Temporary Burn Folder
And plugging in one of those U3 USB drives may add another burning folder, as well as those virtual CD-Rom Emulators...
(I have 4, with 2 physical drives, a U3 USB stick in, and a virtual CD-Rom)