Inventions and Sinfonias
Bach’s Inventions and Sinfonias made heavy use of the counterpoint in his pieces, with many repeated melodies that can be heard in both the right and left hands of the pieces. He wrote 15 of each, each invention and sinfonia is in a different key and thus are at levels of varying difficulty.
Bach’s Invention No. 1, http://solomonsmusic.net/bachin1a.gif
Crab Canon
The Crab Canon is a remarkable composition by Bach that not only uses a form of the counterpoint, but uses it in a unique way, such that the piece can be played forwards and backwards. But not only that, the Crab Canon can be played forwards and backwards at the same time to create a unique harmony and impress many people. This is demonstrated in the video below.
musematics 
