Aviary, a great online resource, has launched Myna. Myna is an online audio editor that is very powerful. People have been comparing it to Garageband.
What I really love about Aviary is 1) it's free, 2) the tools are easy to use and very powerful and 3) everything is online. This means that I can access these tools from any internet enabled device.
Aviary also has advanced image editors and a screen capture tool.
Aviary's tools can be used by students to create some great projects for class, as well as for teachers to create things for their students.