Aviary.com has been coming out with some really cool web apps lately. They released Myna the other day. It is a web-based audio editor. The setup looks similar to Garageband. It imports wav, aif, mp3, wma, m4a, and ogg files. (Really nice selection) You can set the type of license to the recording. It works really well if you are using smaller files that are to be assembled. Multiple tracks can be added to the recording. There is a library that sounds can be pulled from. The compilation can be downloaded as a wav or as a mp3 file.