// doesn't snap back, but doesn't respect the duration of the animation
		CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"transform"];
		NSValue *value = [NSValue valueWithCATransform3D:CATransform3DMakeRotation(M_PI, 1.0, 0.0, 0.0)];

		animation.duration = 3.0;
		animation.fromValue = [NSValue valueWithCATransform3D:layer.transform];
		animation.toValue = value;

		[layer addAnimation:animation forKey:@"transform"];
		[layer setValue:value forKey:@"transform"];