Dynamically link images to actual files
Right now, when I insert an image into a slide, powerpoint keeps a copy of it and doesn't change the image when the parent file on disk changes.
How do I link an image to the file on disk so that everytime I change the file, the corresponding image in the slide also changes.
Answer
Creating an object is the heavyweight way to do things, or can be.
Instead:
Use PowerPoint's Insert, Picture, From File command.
Browse to the picture you want to insert.
To the right of the Insert button there's a downward arrowhead. Click that.
Now depending on your PPT version, you'll see two or three options. Once is a straight link. That'll produce a link to the image file that'll update whenever you open the presentation and PPT finds that the image has changed. And unless you take special steps, the link will break if you move the file, leaving you with a red x instead of an image.
Recommended: If you have 2007 or later, there's a Link + Embed option. That embeds the image in the presentation file (no broken links/red Xs) but still checks the original to see if the embedded image needs updating.