Hmm, not sure if this is just not very well known, or seriously under-discussed, but here I am, sitting in bed on my iBook, marvelling over this cool expose thingy. If you hold down the F10 key, it shows you all of the open windows for the frontmost application. Everyone knows that. But do you all know that if you press tab while holding down the F10 key, it switches to the windows of the next application? I did not... And if you hit tab while holding down F9, it switches you to F10 mode. Not a serious trick, but something that's pretty cool and could be of good use!