The killer setup is a repeater that outputs onto a CB
Imagine a repeater inputing on FRS or MURS (with a PL tone of course), and then outputing on a CB
channel. It would drive crazy the other CBers not on the system. But for such a repeater to be useful, it would need to be located on a hilltop or building-top.
Such a system did exist here in Los Angeles in the 80's. It was a dual-hilltop repeater.
It would input on a hill 50 miles away, in big bear, and then link on 49MHz, and then output from atop palos verdes hill. It was great fun since CBers would drive to palos verdes to jam it out, not knowing that it was linking from another hill via 49MHz.
But such things were not meant to last, and the FCC
eventually caught up with it.