Had an old battery backup die out. Ripped it apart to see the pretty innards, and figured I'd snag a few components off the board for keep sake to play with when I get back into labs. However, I want to make sure the board is not retaining any dangerous levels of electricity. Most of my measurements on several components have been under 100 mV and 30 mV. Do such boards retain lethal amounts of juice, or can I freely desolder components without zapping the begeezus out of myself?