The Sonic Screwdriver is a rechargeable version of the normal Screwdriver, and is used to alter the orientation of Logic Items and Machines from the RedPower mod. It is recharged using Blutricity. One way to do this is to place a fully charged BT Battery next to the Sonic Screwdriver in your hotbar, and right-click with the BT Battery in hand. Sonic Screwdrivers can also be recharged by a Talisman of Repair when placed in the same Alchemy Bag or Alchemical Chest with a Talisman of Repair.
The name and the item itself is a reference to the BBC television series, Doctor Who.