bottle function concepts part 2

see the post below, here are some more quick ideas for second-life functions:

Music shaker/percussion - quite a simple idea, but one that is also very quick to create: put some rice in the dry, empty bottle and away you go!

Timer - a little more complex, playing around with the hourglass concept. The bottle would have to be cut/drilled for this to be achieved. Is this a way forward?
Bird feeder - a bit like blue peter? but valid all the same, again would require the bottle to be altered physically.


It seems that to radically change the function, I may have to alter the shape through a a process: cutting/drilling/etc. Otherwise, I'm limited to what the original designer gives me...