High-end custom knives run from $400 to $40,000. Here's what makes them so expensive, and why they could be worth it. Buying an expensive knife won't turn you into an excellent cook anymore than going to the Container Store will make you an organized person. But well-crafted custom knives are things of physical beauty, and they can have a kind of talismanic power. Super-luxury chef's knives start at about $400, and go up from there. Famously, some custom knives, like those from legendary knife maker Bob Kramer, sell for upwards of $500 an inch. At auction, Kramer's knives often fetch...