Sibelius - Sibelius is a virtual score creation tool which allows composers to easily create new piano scores, developed by Avid.

AudioTool - Whether you want to make music for the club, or you're aiming to put a few tracks to a film, Audiotool is a website geared towards putting the mixes at your fingertips. Read more about AudioTool.

MuseScore.org - Create, play back and print beautiful sheet music with free and easy to use music notation software MuseScore. For Windows, Mac and Linux.

LinuxSampler - LinuxSampler - free, open source pure software audio sampler with professional grade features.

Finale - Finale, the world standard for music notation software, lets you compose, arrange, notate, and print engraver-quality sheet music.

Samplr - Samplr app for iPad lets you make music and play with sound by touching it with your fingers.