My apologies for being a smart ass, but just in case you ever want to learn German, visit Germany or boast about your profound knowledge:

handlich = something is useful because it is easy to handle, for it can be comfortably held/operated by hand (e.g. vacuum cleaner, book, suitcase)

nützlich = something is useful for a certain purpose (e.g. invention, domestic animals, your Neanderthal clothes)

praktisch = something is useful because it makes tasks/things easier/securer/quicker/etc. (e.g. advice, car, piece of furniture)

"Nützlich" and "praktisch" can often be used synonymously, whereas "handlich" can only be used when the hand is involved. :D