gistfile1.cs

// a generic wpf boolean value converter class
public class GenericBooleanConverter : IValueConverter
{
        public object TrueValue { get; set; }
        public object FalseValue { get; set; }

        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            return TypeDescriptor.GetConverter(targetType)
                .ConvertFrom((bool)value ? TrueValue : FalseValue);           
        }

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            var convertedTrueValue = TypeDescriptor
                .GetConverter(targetType).ConvertFrom(TrueValue);

            return convertedTrueValue.Equals(value);
        }
}


<!-- usage -->
<GenericBooleanConverter x:Key="booleanToVisibility" TrueValue="Visible" FalseValue="Collapsed" />
<GenericBooleanConverter x:Key="boolToOrientation" TrueValue="Vertical" FalseValue="Horizontal" />


<StackPanel 
   Orientation="{Binding IsMyViewModelVertical, Converter={StaticResource booleanToOrientation}}" 
   Visibility="{Binding IsMyViewModelVisible, Converter={StaticResource booleanToVisibility}}">
   <Label>I am a label that is sometimes visible</Label>
   <Label>I am a label that is sometimes to the left and sometimes below the previous label</Label>
</StackPanel>