These clever slings from Edelrid have proved popular with trad climbers in recent years.
Firstly they are thin - only 6mm, but more importantly they are stiff. This means you can reach with them, perhaps to lasso a spike or peg.
They are also great for tricky little threads that might otherwise require two hands, or perhaps just not be possible. You can actually bend these into a hook shake to get into placed that a floppy sling just won't reach.
They are also a lot hardier than a normal dyneema sling and should last longer.
More expensive that a normal sling but I can forsee most trad climbers carrying one of these in a 60cm length in the next couple of years.
I look forward to getting some reviews of these on here...