red kangaroo

most of the time they aren't aggressive
though these guys can be pretty tough, and sometimes a bit territorial (males)
platypus:

bit of a strange creature. it's a mammal that swims, lays eggs, and has a duck's bill
*edit*
dingo:

these guys used to be hunted a lot, but not so much now.
Koala:

they look cute and cuddly, but they do have sharp claws
Wombat:

usually pretty friendly, though sometimes a bit shy
Echidna:

these guys are ant eaters. and, you wouldn't want one in your bed.