nice to have muO (musical Objects I think) preloaded in an image. No need to figure out this for myself. A real time saver.
If you want to have a better feel of muO, a recent version is also available as a ready-for-use image at: http://www.zogotounga.net/comp/squeak/sqgeo.htm (direct link: http://www.zogotounga.net/comp/squeak/muo/muO%20243%20image.zip)
Stef