> For example, I have a for loop that keeps requesting a new pointer...

Unless you put that pointer in a structure which lives forever, it will be freed as soon as a loop finishes:

    struct Foo { a: int, b: int }
    impl Drop for Foo {
        fn drop(&mut self) {
            println!("Drop {:?}", *self);
        }
    }

    fn foo(i: int) -> Foo {
        println!("Creating Foo with {}", i);
        Foo { a: i, b: 5}
    }

    fn do_thing(foo: &Foo) {
        println!("\tdo thing {:?}", *foo);
    }
    fn do_other_thing(foo: &Foo) {
        println!("\tdo other thing {:?}", *foo);
    }

    fn main() {
        for i in range(0, 5) {
            let a = box foo(i);
            do_thing(a);
            do_other_thing(a);
        }
    }

will print

    Creating Foo with 0
        do thing Foo{a: 0, b: 5}
        do other thing Foo{a: 0, b: 5}
    Drop Foo{a: 0, b: 5}
    Creating Foo with 1
        do thing Foo{a: 1, b: 5}
        do other thing Foo{a: 1, b: 5}
    Drop Foo{a: 1, b: 5}
    Creating Foo with 2
        do thing Foo{a: 2, b: 5}
        do other thing Foo{a: 2, b: 5}
    Drop Foo{a: 2, b: 5}
    Creating Foo with 3
        do thing Foo{a: 3, b: 5}
        do other thing Foo{a: 3, b: 5}
    Drop Foo{a: 3, b: 5}
    Creating Foo with 4
        do thing Foo{a: 4, b: 5}
        do other thing Foo{a: 4, b: 5}
    Drop Foo{a: 4, b: 5}

(drop is ~equivalent to a C++ destructor)