Add a few constants to the ModelNode class to hold unmodifiable nodes for a few common cases:

public static final ModelNode TRUE = new ModelNode(true).protect();
public static final ModelNode FALSE = new ModelNode(false).protect();
public static final ModelNode ZERO = new ModelNode(0).protect();

Specific use case is the hundreds of examples of this kind of thing in WildFly where we could use a constant for declaring default values:

static final AttributeDefinition FOO = new SimpleAttributeDefinitionBuilder("foo", ModelType.BOOLEAN)
    .setRequired(false)
    .setDefaultValue(ModelNode.TRUE)
    .build();