Not looking to nest it. I'm looking for a cup/mini pot with a flush lid that the canteen will sit on top of. My bottle holder is the 12X5 Maxpedition. The Klean Kanteen 64.oz bottle is about 8.6" tall and 4.5" in diamter. With the Maxpeds padding about 4.75" in diameter is as large as I can probably fit in there. So I'm looking for something that is around 4.5" in daimeter and around 3" tall with a flush lid so that is will utilize the remaining room. If I can't find anything I'll just get a round tin for storing drink mixes and water tabs and such. But it sure would be cool and it were a piece of cook ware so that I could still store stuff and use it to boil or cook in. Hope that helps a little better. I don't think I was descriptive enough. And thanks so far for all the great advise.
But the nest idea is interesting. That way I could have the pot, with lid underneath and still slide a tin underneath for storage, Hmmmmm. But that being said I'd still rather have a titanium pot or covered mug for storage over a tin.