As so often is the case, it's the little things that make a big difference. You may know that F5 has long started a powerpoint slideshow, while you were editing a powerpoint file. But it starts at the beginning of the show.
What if you're editing slide 22 and want to start there to see how things look? You may know there's a little (tiny) icon in the bottom left corner to cause it to start the show there, but for folks who are keyboard fans like me, it was always an annoyance.
Imagine my delight, then, to learn that Powerpoint 2003 added Shift-F5 as a means to start the show from the current slide. Halleluiah! :-)