The eye of sauron?
Kim has one of those. I tihnk it is a radbot 1000
That's the one. I've stopped using it on group rides (except in city traffic), as for every "That's really cool - flashing, but not headache-inducing" there's a "I keep getting distracted by your sinusoidal throbbing", even with it mounted at axle-height, well below the eyeline of a following rider. The 4DToplight is perfectly adequate in that sort of situation anyway.
I use it when I'm on my own, though, as a recumbent lacks many 'bicycle' cues when viewed from behind, and it seems like excellent insurance against accusations of invisibility. It's also good (in super-obnoxious mode) for fog and heavy rain in daylight.
If an audaxy n+1 ever happens, I'm going to come up with a rear lighting solution consisting of a moderate brightness high-surface-area static light, with an obnoxious flashing laser of death that can be easily switched on and off from the handlebars according to need.