Now that fall is here it's time to make stock again. (Maybe I should have started out with, while the market is down, it's time to make stock?) (But since I started out by talking seasonally, I should add that yes, I know it's been fall for some time now--but there's some lag time between my personal universe and the big public one.)
Here's my stock-keeping system: I put my giant stock pot, empty, in the chest freezer in the basement. As meals get cooked and eaten upstairs, bits of onion peel, asparagus ends, chicken bones, parsley stems, carrot peels, wrinkly cherry tomatoes, and other miscellany are set aside, and dumped in the stock pot to freeze. When the pot is full to the brim with jetsam, I bring it upstairs, fill it with water in the sink, and heave it onto the stove (remembering, of course, to lift with my legs). I add nothing else. For a few hours, it simmers merrily. The next day, after a suitable cooling-off period, I put the pot back in the sink (for easier reach and less clean-up), and the detritus is removed. The stock is ladled into plastic quart take-out containers to be frozen and used later in soups and such.
I don't add anything extra to the stock, and I don't keep track of what's in there. Most bits of vegetable and meat are fine, and some fruits, such as apples, which are not too sweet. I usually don't add fish bits. Each batch of stock is slightly different, but somehow it always tastes good. I did have to dump a batch once because I had put several lemon rinds in, and somehow boiling them gave it a weird and unpleasant taste, but that's the only flavor failure I've had. usually it even makes good soup on its own, with a little salt and a squeeze of lemon, and two or three nice big matzo balls.