If you are using InDesign CS3, you have probably noticed that the Transparency palette is gone, and is replaced by the new Effects panel.
Among the new effects in this panel is the Gradient Feather effect, which is great for fading a photograph into a white page or a colored frame beneath the photo.
What you may not have noticed is that there is also a Gradient Feather tool, buried underneath the Gradient Swatch tool in the tool panel (or press Shift-G. This tool allows you to control the direction and length of the Gradient Feather effect interactively. More information about the Gradient Feather tool can be found here.