This recipe (linked above) by Michael Chu is fast, simple, and makes a delicious mayonnaise! (and the comments are very informative, too!)
Normally, I just crack open a jar of Hellmans/Best Foods mayo and use it, but since I'm going to be using a lot of egg whites to make meringue and some Chocolate Chiffon Cupcakes, I thought it would be a good way to use the extra yolks.
Plus, it's going to make the googly-eye deviled eggs I'm making for Halloween really yummy! ;-)