If you ever get the Nortel ad at the top of the page, refresh and scroll down before the ad reappears. depending on how far down you scroll, the add shrinks that much, to where if you pass it, it disappears.

NOTES:

1. By "shrink" I mean it acts like a frame, with a scrollbar on the side, till it disappears, and it stays that size until you refresh at another size.

2. This is in windows XP and IE 6

3. I've only tested the nortel ad, don't know about the others.