I (regretfully) gave some of them away to a certain collector, but the rest I jealously hoard in my Megaton shack, sorry, mansion As I have only found a single blueprint I have not made any grenades yet and I currently have exactly 30 bottles
Usually try and place them somewhere for show. Until one bottle knocks off the rest *sigh*. Reminds me of a song but with slight edits '99 bottles of nuka cola quantum'.
With the perk to turn 10 nukas into a quantum (Wish it wasnt automatic but I digress) I have about 100+, including a nice pile of nuka-nades. I got a lot of them standing around my nuka machine with various nuka cola paraphenalia.