If you want to download these, unzip them anywhere, and you can find them using File | Scripts | Browse... from Photoshop.
If you think you want to keep them, you should put them in your scripts directory, and they will be available on the menu.
I use this script as the final step before I print a picture to display at work, where everyone likes to see the camera settings in effect when the picture was taken. This script will put a small black border around your image, a copright caption, and a line containing EXIF information. Here is a small example (note that it is not intended to be used on such small images). This should also work on a Mac, but I have no way of testing it.
My new camera has the ability to store GPS locations in the EXIF header. Much software can display them. This script looks for the EXIF GPS information, and if it is present, opens a web browser with a map site directed to display the location. It is set to use MapPoint by default, because it lets you put a push-pin at the location. If you change the code, Google Maps is also supported. This will only work on Windows, because it has to create a temporary shortcut file (TemporaryPhotoshopMapUrl.url in your "home" directory) to launch the web page.
This script puts any image in the lower-left corner of the active document. To use it, put the image in a file called signature.psd on your desktop. You can change the location of the file, or the location of the watermark by editing the script.
Constrained cropping. This is good for wallpaper, or printing traditional 4x6, 3x5 or 8x10 images. It won't crop -- it will just create a selection rectangle which you can move around with the mouse after selecting the "Rectangular Marquee Tool." Then select Image | Crop.