Best would be a FC tailswitch, like on the P30 or L2M hosts if you prefer drop-ins (1-mode, N-modes, whatever).
Something like a GTmicro or GTmini with diffusion film would also work in momentary mode (5 clicks to start, untwist/retwist tailcap to go back to regular modes).
Nice score if you can find ’em, but the Nitefox UT20 has a dual-switch setup, sideswitch for setting the mode, FC tailswitch to let you get momentary bursts in that mode.
Any light, especially throwy ones, you can slap on some diffusion film to make it a flooder and get a nice wiiiiiide area of light in dark dingy cabinets and the like. No need to be blinded by overly-bright hotspots washing out everything else.