There are people who say things like its not the voltage that kills its the current but through the human body under normal conditions it takes a decent bit of voltage to induce enough current to really hurt you. Watch out for things with large capacitors and large voltages. If you want to take something like that a part let it sit for a long time for the capacitors to discharge. I worked at a TV repair shop in high school dismantling tube TVs for scrap components. The first step after opening was to use a large screwdriver to discharge the flyback transformer.