For sale is an early Shunyata Guardian with four outlets and an attached Diamondback cord. Note that these days, Shunyata power conditioners come without cords, and necessitate a rarer cord with 20A receptacle (min $120 new).
It would be tough to get 4 outlets of Shunyata power conditioning and protection for less than this.
SOME ADDITIONAL SHUNYATA INFO:
As I understand it, the Guardians are the pro versions of the Hydras, which don't look quite as pretty...
And here is what Grant from Shunyata just wrote in an Audiogon post:
The life expectancy of the Hydras is indefinite. They do not generate heat and are passive in operation. The only thing that can go wrong would relate to a weather or surge related event and we will replace the protection free of charge for the life of the unit. That has happened only 4 times in twelve years world-wide. There is no pressing need to upgrade what performs well. Obviously, we are a "research" based company and its the nature of our business, so evolving and creating better performance is what we do. No need to apologize for that.