var animating = false, 
        effect_in = false, 
        effect_out = false; 
        
    Event.observe(window, 'load', function() 
        { 
            Event.observe($('twitter'), 'mouseover', function() 
            { 
                if( typeof effect_out == 'object' ) 
                { 
                    effect_out.cancel(); 
                } 
                effect_in = new Effect.Morph('twitter', 
                    { 
                        style: { 
                            left: '0px' 
                        }, 
                        transition: Effect.Transitions.spring 
                    } 
                ); 
            }); 
            
            Event.observe($('twitter'), 'mouseout', function() 
            { 
                
                if( typeof effect_in == 'object' ) 
                { 
                    effect_in.cancel(); 
                } 
                effect_out = new Effect.Morph('twitter', 
                    { 
                        style: { 
                            left: '-240px' 
                        }, 
                        transition: Effect.Transitions.spring 
                    } 
                ); 
            }); 
        } 
    );