I find the gnu especially handy when being hassled by lions while riding my mtb in the Serengeti, although it requires getting a new gnu now and then to satisfy their appetite. I´m all for the gnu control that the lions enforce, especially since I got my gnu license the lions dont bother me much anymore.
I've heard that the hot set-up in the pro peloton is to carry a lighter-weight Asian antelope or gazelle instead of a gnu. It's not recommended for heavier riders though.