Found this while I was looking for an ice pack – the kind you can put ice into, not the gel like stuff you keep in the freezer. This was better than both those ideas though not quite as useable for ice packing sore parts LOL. But! Look at this – it has a narrow capped top for drinking out of (narrow so you don’t slobber it all down the front of you) and a wide screw off part just at the shoulder of the thing so you can actually clean inside.
How brilliant is that? About $10 at Target.