1. Highlight but don't open the icon you want to rename.
2. Right click.
3. Choose "Rename."
4. Delete the old name in the box and type in the new one.
5. Click and leave your work for others to see.

You can do the same thing with folders. Just be aware that if a program is looking for a certain folder and you've renamed it the program won't work.

I've done things like renamed ie.exe to "poopsy.exe" when I didn't want the public to access Internet Explore.