Musician's Practice Edge is an Australian company that creates software to help musicians reach their musical goals through better practice.

Currently we have just one product, which is called Musician's Practice Edge (Windows only currently).

It's designed for musicians who have bought a lot of educational materials (videos, audio, books) and want to get more out of them.

It does audio slowdown (free), video slowdown and zooming ($29.99)
Both free and paid versions also have:
Key and Tempo trainers (step through a loop a specified number of times each time adjusting speed and/or pitch. can use/set patterns for the key changes - e.g. circle of fourths, chromatic ascending, random)
Named loops
Associate pdf charts, jam tracks, and your own notes in Word or notepad
Import existing course materials (optimized for TrueFire courses)