Microsoft has managed to patent the double-click. But not the double-clicking of a mouse on a PC (whew!. Fortunately
the patent really only covers double-clicking or holding down a button on a handheld. Which is enough to annoy anyone
who has ever double-clicked with a Palm, but the patent is supposed to apply to such a limited context (i.e. on a very
specific kind of PDA under very specific circumstances) that it's unlikely (we hope) that Microsoft will ever use it to
strongarm PDA and smartphone makers.
PS - Scott over at Tapland has some more thoughts about this.