Here is a handy idea, its pocket knife so it is already handy as a tool! However, it also has a cork handle and that means if you happen to drop into water like a pond or the like, instead of sinking to the bottom like a stone it will float allowing you to retrieve it with ease!
These are the details on the pocket knife that floats;
The Cork Knife eliminates any fear of cutting rope on the side of a lake or whittling wood over a creek. The cork handle on the stainless steel blade allows the knife to float when dropped in water. It’s the ideal companion for any crazy outdoor trek or fishing expedition you might be planning.
This handy floating knife is going to cost your around $26 (£17).
Source: Cool Material