It's hard not to be impressed with the work of Great Britain's Brook, who's known primarily for his hurdy-gurdies but does build a complete line of mandolin-family instruments. The acoustic mandola/bouzouki on the left has built-in Headway electronics (including a pickup switch hidden in plain sight on the bridge), while the "bassuki" on the right combines a bass and a bouzouki. Tuning on the latter beast would be GGDDAAEE EADG, which is bound to blow your mind.