If you spend lots of time working with PowerPoint, you'll want to check out this free resource offering all the keyboard shortcuts you can use in the program to save time and boost your productivity.
You can download a free/donationware ebook with all the shortcuts or just check out the full list at Indezine. These were created by Microsoft PowerPoint MVP Geetesh Bajah, and they include the keyboard shortcuts for PowerPoint 2003, 2007, 2010 and 2013.
Most of them are actually keyboard sequences, where you press two keys together, like a regular shortcut, and then release and hit one or more keys.
You'll find shortcuts for bringing up the animation task pane (ALT+A > C), distributing slide objects horizontally (Alt+H > G > A > H) and switching PowerPoint views (Alt+W > [other keys]), among others.
It's a great resource for all you presentation ninjas out there, and makes a nice companion to the Excel keyboard shortcuts reference sheet and the Word shortcuts cheat sheet.