The clue was my video card, it screams whenever I run AH or the TE.
This is repeatable on my machine. Launch the TE but while it's still drawing the editing window, click the close box in the corner.
No sign of the TE running from my desktop and the Task Manager doesn't show it in the Applications window, but open the Processes tab and there it is, ahedit.exe *32 happily processing who knows what at 492,916k. End it in Task Manager and the card fan slowly decreases in noise but I don't think it goes away completely. Not in a reasonable time anyway.
