The kind of items you need to save are quite obvious, I found. Things that come from rare animals often, and things that don't have any other clear purpose, and that sell for 1GP. Particularly if it's some part of a creature's body that a creature of that species always drops when it dies. Ettercap silk glands, Fenberries, Fire Beetle bellies, Skeleton knuckles, Gargoyle skulls, Rakshasa eyes, Special Holy Water, IronWood. There are plenty of walkthroughs and game guides that list the things on various sites. Unfortunately, I didn't find the items of much use. I don't think I was ever able to make an item that I hadn't already found or seen for sale in a shop. There is a ring on protection +3, but by that stage I already had several of +3 or better. There is an amulet of natural armour +5, which would be useful if you didn't already have one. Boots of the Gargoyle aren't bad, but I already had a couple of pairs of those plus a couple of better pairs I think
