Java Puzzlers

Hi
see this .. best java puzzles ever
http://video.google.com/videoplay?docid=9214177555401838409
wat say ??

Adding my bit of cheese on it try predicting output of

class Some_Runnable implements Runnable {
    public void run() {
        System.out.println("Some_Runnable");
    }
}
 
class Some_Thread extends Thread  {
    Some_Thread() {}
    Some_Thread(Runnable r) {
       super(r);
    } 
    public void run() {
        System.out.println("Some_Thread");
    } 
}

class Some_Other_Thread extends Thread  {
    Some_Other_Thread() {}
    Some_Other_Thread(Runnable r) {
       super(r);
    } 
    public void run() {
        System.out.println("Some_Other_Thread");
    } 
}

class default_thread extends Thread {
    default_thread() {
        System.out.println("IN default thread ");
    }
    default_thread(Runnable r ){
        super(r);
    }
    // NO RUN() METHOD
}
 
public class Class2  {
    public static void main(String args[]) {
        // lang.Thread class implements Runnable
        new Some_Thread().start();
        new Some_Thread(new Some_Runnable()).start();
        new Some_Thread(new Some_Other_Thread()).start();
        
        new Thread(new Some_Runnable()).start();
        new Thread(new Some_Other_Thread()).start();
        
        System.out.println("Default Thread ... doesnt override run()");
        new default_thread().start(); // ok
        new default_thread(new Some_Runnable()).start();
        new default_thread(new Some_Other_Thread()).start();
        
   }
}