A bench is provided for use by at least two persons of similar or differing heights. In some embodiments, the level shifting circuit includes a clocked level shifter. The scope of the first virtual screen is determined according to the configuration parameters of the first virtual screen. The lower level of cache memory, responsive to receipt of a memory access request that hits only a partial cache line in the lower level cache memory, sources the partial cache line to the at least one upper level cache memory to service the memory access request. A pre-existing authentication channel established between the authorizing party and the trusted third party is used to authenticate the authorizing party.