There are typically options when cycling as nature provides materials that can be utilized in most areas I ride even if they're not awesome.

The reason this idea intrigues me is I'm sometimes high up on a mountain or in a "blue bag" area (where you are required to carry out anything you might drop...) where conditions could be gnarly or you'd just as soon not have the stuff in your backpack.

I typically use caloso's method, but it's not bulletproof and this this other method is. However, cramping/bonking can be real issues at decent levels of exertion over many hours so I'm wondering if it's a good idea, bad idea, or neither here nor there.