2013-03-17 suprised hadn't caught main bug earlier, not allowing, e.g.,

    ArrayList<remote X>

also tested some related stuff, which I'm leaving here since I'm not
sure we test for it elsewhere.

For the 2x tests:

    shouldn't be able to cast remote to local
    can always have op in remote return this, as in 22
    and should leave that up to user since 22 won't work if on diff VM, see 23
    but if make serializable then it will
    but need to be careful as in 24
