Deer? Bug? Deer Bug!?

We went on a hike to Mt Takao today. It was hot in the city, but very nice and cool out in the forest and the mountains! Takao is wonderful in that it has been inhabitated by monks for almost 1000 years. Hence, the forests and rivers are protected and pristine old growth, with some trees easily over 1000 years old (giant cedars). This is amazing to see here, as the mountain is only 45 min away from downtown Tokyo!

We spotted this strange looking bug in the forest. Its antennae were really interesting! I have never seen anything like it. Anyone know what this insect is?