Download the You've Got Mail screen saver, featuring stills and quotes from the film. Just select the right computer screen for your system and follow the instructions below.
Macintosh
Macintosh (.hqx)
Windows
Windows (.zip)

Instructions:

On the Macintosh, click to download the file, which will unstuff itself on your hard drive (if it doesn't, use Stuffit Expander). Drop the unstuffed file into the Control Panels folder in your System folder, restart your computer, and you're all set. (You can adjust the screen saver settings by accessing the Control Panels in your Apple menu.)

In Windows 95/98/NT, download the file, which will unzip to create a file called "ygmsaver.exe". (If you don't have an unzipping utility, you can get one here or here.) Double-click this file and it will self-install. Access the screen saver settings in the Display control panel, and you're all done.