amphetype - Advanced typing practice program
typing.io - Typing.io is a typing tutor for programmers. Practice typing the hard-to-reach symbols in code.
TypingMaster - Learn touch-typing technique, and improve/increase typing accuracy and speed.
Typing Speed Test - A simple typing test to see how fast you can type
Type Fu - Type Fu is an app that will teach you how to type fast. The right way. On Mac, Windows and Chrome OS.
KeyKey Typing Tutor for Mac - Hone your keyboard skills without the hassle