Hi guys, i made, with some mix of research and " trial and error",
a relative good and fast formated time to draw an applet;

in this implementation i formated only seconds and milliseconds:

assuming you already do in setup():

1. public void setup(){
2.       loadFont();
3. }

you can put this function in draw()

1. protected void drawSeconds(boolean draw){
2.         if (draw) {
3.             text(getFastFormatedTime(), width-(mPFont.getSize()*9), (float) (height-(mPFont.getSize()*0.5)));
4.         }
5.     }   

1.     protected String getFastFormatedTime() {
2.         /*  with some crazy calcs... (my cat and this are reference:
3.          * http://en.wikipedia.org/wiki/Modulo_operation#Performance_issues  :P)
4.          * i found good formating with seconds and milliseconds:
5.          *
6.         int t = (millis() & -2)-1;
7.         String s = String.valueOf(t).substring(0,String.valueOf(t).length()%4+1)+":";
8.         String ms = String.valueOf(t).substring(String.valueOf(t).length()%4+2,String.valueOf(t).length()%4+4);
9.         return s+ms;
10.     }

anyone can help with some better algorithms?

Thanks