The Lastolite Tri-Flip 8:1 Kit is such a versatile piece of gear that you really shouldn't be without one. The kit consists of a Tri-Grip Diffuser and two Tri-Flip sleeves which are reversible. So although you don't get eight sleeves like shown in the Lastolite photo above, you do get eight sides, seven reflective surfaces and one subtractive (black) surface.
The Diffuser is an absolute must when you're shooting outdoors in bright sunlight and need to get rid of squinting eyes and harsh contrasts. The reflector sleeves are the icing on the cake and the variety in the different temperatures of reflected light is everything you will ever need. From soft silver to gold and everything in-between - if you only buy one reflector, this is the one you should have in your kit.
I have a lot of Lastolite gear, from the small XpoBalance and softbox's, to the fantastic Hilite illuminated background. There is something in the Lastolite product range to suit every lighting situation. My next purchase will be the 100cm Umbrella Kit (maybe I'll do a review here in the near future).