If it is ok to exploit the question a little bit, then I will add some new Java. The trick is for sure not new, but perhaps interesting that this is possible in Java.

	static void pleaseDoNotDoThis() throws Exception {
		Field field = Boolean.class.getField("FALSE");
		field.setAccessible(true);
		Field modifiersField = Field.class.getDeclaredField("modifiers");
		modifiersField.setAccessible(true);
		modifiersField.setInt(field, field.getModifiers() & ~Modifier.FINAL);
		field.set(null, true);
	}

	public static void main(String args[]) throws Exception {
		pleaseDoNotDoThis();
		doit(1);
		doit("NO");
		doit(null);
		doit(Math.PI);
	}

	static void doit(long x) {
		System.out.format("(x == x + 2) = (%d == %d) = %s\n", x, x+2, (x == x + 2));
	}

	static void doit(String x) {
		System.out.format("(x == x + 2) = (%s == %s) = %s\n", x, x+2, (x == x + 2));
	}
	
	static void doit(double x) {
		System.out.format("(x == x + 2) = (%f == %f) = %s\n", x, x+2, (x == x + 2));
	}

And the results:

    (x == x + 2) = (1 == 3) = true
    (x == x + 2) = (NO == NO2) = true
    (x == x + 2) = (null == null2) = true
    (x == x + 2) = (3,141593 == 5,141593) = true
    (x == x + 2) = (Infinity == Infinity) = true