Cork from wine bottles.......

A great place to store hooks.(it floats if you drop 'em) You can also tie your hook and leader on there as well.

It can also serve as a back-up drain plug on your yak. (you'll need to re-shape it to a smaller size with your knife of course)

I've found that wine corks work great as sabiki keepers.  And they give me more excuses to drink more wine!

-Allen

Another use for wine corks is trolling in weedy conditions with seaweed on top of the water. You cut a slit down the wine cork and put it on your line. Then it floats on top and catches the crap that tries to slide down your line.