Hi snorro, I haven't heard any more about this issue so unfortunately I can't help. Might be some crazy bugs flooding the net that can't be found or stopped yet!

To reduce the annoyance, have you tried using a different browser i.e. Firefox? See if the problem is reproduced? Also have u checked Windows Knowledge Base, Support Forums, or Yahoo's Support Forums (not sure if they have one but usage of Yahoo! seems to be a common denominator in these problems.

Also another thing, have u tried uninstalling and re-installing IE? Also a System Restore might help, to the time before the problem began.