Use this super-secret method to access some super-secret advanced editing modes in iPhoto6:

1. Enter edit mode for any image.
2. Select the Retouch or Red Eye tool.
3. Press Caps Lock, Control, and 9 at the same time, then release them.
4. Press Tab. If you activated the Red Eye tool, the small cross hairs will be replaced with a large oval. If you were using the Retouch tool, your cursor is now a small dotted circle with "0.50 { }" below it.
5. For either tool, press the "[" and "]" keys to alter the size of the area the brush covers.

[robg adds: In testing this hint, I found a couple of other tidbits. First, the Retouch tool has a Lighten mode -- activate it by hitting Tab a second time. Second, when you're in the Retouch mode, you can use the "{" and "}" keys (as noted by the cryptic label) to change the intensity of the retouch effect. Crank it to 1, and it's very strong; at .10, it's barely noticeable. Here's what each of the edit cursors looks like:


(I also recorded a short movie showing each cursor being resized.)

If you edit in a separate window, then this mode will be reset each time you enter edit mode. If you edit in the same window, though, it will remain enabled until you quit iPhoto. I found it easiest to press and hold Control, then add Caps Lock (hold it down), and then press and release 9. After that, Tab should cycle the tool. Make sure you have one of the two edit tools selected first, or nothing will happen.]