Lowes offers Spyder Stinger 6-Piece 6" Woodboring Spade Drill Bit Set for $8.98 (reg $14.98). Free shipping on orders over $35. 

Product Description:
The Spyder Stinger™ spade bit features an innovative non-clogging, automatic-feeding precision tip for optimal speed and accuracy. This patent pending tip automatically engages the work surface for no-thrust drilling. Unlike other spade bits with a self feeding thread point, the Stinger™ spade bit won’t clog, won’t wander and drills up to 20x faster. Chuck them into your impacting tool for even greater drilling power on soft and hard woods.

• 20X faster and 10X more holes per charge than conventional spade bits
• Stinger™ threaded tip automatically engages the work surface for no-thrust drilling
• 1/4-In impact rated speed hex won't slip in the chuck and is ideal for use in quick change battery powered impact drivers
• Stinger™ thread point won't clog, or wander, and drills faster than conventional spade bits.
• 6-In overall length
• Set contains: 3/8, 1/2, 5/8, 3/4, 7/8, 1-In bits