In my little scripting language I have found the following extension to the new construct very useful.

//-- make a little test class
class Foo
{
    float value;
}

//-- the sugar
Foo foo=new Foo()
{
    value=9;
}

Which is equivalent to going:

Foo foo=new Foo();
with(foo)
{
    value=9;
}

By itself it isn't too exciting, but when combined with operator overloading and anonymous functions it becomes an intuitive way to build hierarchial objects in a data desciption style.

MenuBar menuBar=new MenuBar()
{
    menus+=new Menu("File")
    {
        menus+=new MenuItem("New")
        {
            onClick=function(Menu menu){goNewFile();}
        }
        menus+=new MenuItem("Exit")
        {
            onClick=function(Menu menu){exit();}
        }
    }
    menus+=new Menu("Edit")
    {
    }
}

Another example:

Widget widget=new Widget()
{
    layout=new FlowLayout();
    childs+=new Button("Hello")
    {
        onClick=function(Button button){printf("Hello");}
    }
    childs+=new Button("Exit")
    {
        onClick=function(Button button){exit();}
    }
}