Groupon offers the Pursonic S450 Deluxe Sonic Toothbrush for $41.99. Coupon code "VISA5" cuts that to $39.89. with free shipping. That's the lowest total price we could find by $20, although we saw it for $8 less in June. It brushes at 30,000 strokes per minute and includes 12 extra brush-heads and UV sanitizing chamber. Deal ends October 4.