Originally Posted by troyz 
A 3-way rubber hood (such as a Hama Tele-matic) would also block more light than the generic hood, but it takes longer to fully unfold and the filter thread is larger (e.g. the 67mm hood takes a 72mm filter) so you might want to carry an additional lens cap.
That could actually, by happenstance, turn out to be darn handy for me. 72mm is my 'big' filter size, and a hood with built in step ring wouldn't be the worst thing ever for me, depending what I come up with for zoomage. Is there any sort of listing out there what combinations of these are out there?