InDesign CS3's great Multiplace-and-Replace.
One of Adobe's highly touted features in InDesign CS3 is the ability to place multiple graphics at a time. InDesign provides small preview of each graphic next to the place cursor. You can cycle through your loaded graphics by pressing the right or left arrow keys until you reach the one you wish to place. You can even remove a graphic from the list by hitting the Esc key.
What I didn't realize was that if you hold down the Option key (Alt key on a PC)
and click on a graphic frame — it will replace the existing graphic with the new one you currently have loaded! This Multiplace-and-Replace combination is a terrific time saver for designers who produce catalogs, or other projects with a large number of placed graphics.
Source: Special thanks to James Dempsey and his terrific Creative Guy blog where I first discovered this hidden InDesign replace twist. We should also credit the artwork of icon developer Kevin Andersson and his Sports Illustrated icon set we used to demonstrate this technique.