3DXM new version
Mathematicians Richard Palais and Hermann Karcher, have released a new version of their math visualization software, the 3DXM. The main change is that it now has button-like interface in place of menus, where each button is a icon of the surface or math subject. This makes it much more attractive, and easier to use. Check it out.
Note: the new version is for Mac only. For Windows or Linux users, there's always the Java version at the same download location. Though, the Java version has only some 50% of surfaces or other math objects.