To install a mod, download the Jar file from here, then go to your %APPDATA% folder, then open the .minecraft folder, and place the Jar file in the Mods folder.
More Ways To Minecraft by Ruaidhri:
New items: blue, red and green lightsabers and a ruby. New recipes to create lightsabers.
Money Mod by Luke:
New items: multiple coins and notes and a credit card. New recipes to create one type from another.