What are some Halo 3 tricks

Get a large open crate that you can fit into easily on Last Resort, put in two of the stone barricades, pick up a grav lift, go inside and deploy it. When you do this the crate will fly up like a rocket and floats really high up. This can be a really good sniper tower. But be careful you don't rocket too high up or you will die when the crate reaches the top.