At UKC, many machines use the locally-developed psu suite, which is sort
of like sudo except that it allows each user to choose their own
passwords for each account they can su to, and doesn't have sudo's
command-limiting facilities.
However, if you've got ssh, you don't really need su at all: just
generate each wheel user a keypair for root, and tell them to set a passphrase
as they want for it.
You can do command limiting by using options in authorized_keys.
You can also use ssh as a general notification mechanism; for instance, our router has an old modem plugged into it, and runs xringd set up to ssh to my machine using a key that invokes a command to play a phone ring whenever the modem detects a ring.