One Quickie
  
  
 Finding the height of the title bar
Finding the height of the title bar (NSWindow->General)
   When you setFrame: for a window, you have to account for the height of the title bar.  In the Classic days it was 16 pixels.  In Aqua-land, it's currently 22 pixels.  But that's not safe to use, so try this instead:
- (float) titleBarHeight
{
    NSRect frame = NSMakeRect (0, 0, 100, 100);
    NSRect contentRect;
    contentRect = [NSWindow contentRectForFrameRect: frame
                            styleMask: NSTitledWindowMask];
    return (frame.size.height - contentRect.size.height);
} // titleBarHeight
Rainer Brockerhoff points out that this might miss any system-suppled window decorations at the bottom of the window.  There aren't any now, but Mac OS X 10.37 Sabertooth might, so you may want to take into account the y positions of the original rectangle and the newly calculated content rect.