From 9to5Toys.com:

Today only, until 7 pm ET, Best Buy takes 20% off iTunes eGift Cards, as listed below. At up to $20 off and no shipping, each is tied with our mention from four weeks ago and at or near the lowest price we’ve ever seen. Sales tax is added where applicable. The gift cards will be emailed for redemption so those overseas with US iTunes accounts can take part.

  • $15 iTunes eGift Card for $12
  • $25 iTunes eGift Card  for $20
  • $50 iTunes eGift Card for $40
  • $100 iTunes eGift Card for $80

iTunes credit can be used for Mac Software, iOS Software, Games, iBooks, music, movies or just about anything besides hardware.

  • iTunes eGift Cards: 15% off, $25 eGift Card for $22, $50 for $43, more (9to5toys.com)
  • Three $10 iTunes Gift Cards for $26 + free shipping (9to5toys.com)
  • iTunes $100 Digital Gift Card for $60 (9to5toys.com)
  • iTunes $100 Digital Gift Card for $80 (9to5toys.com)
  • 15% off iTunes eGift Cards: $25 gift card for $21, more (9to5toys.com)
  • $50 iTunes gift card for $40 delivered through email (9to5mac.com)
  • Two $50 iTunes Gift Cards for $80 + free shipping, $100 Digital Gift Card for $80 (9to5toys.com)
  • 15% off Apple iTunes Gift Cards at Best Buy (9to5mac.com)
  • 20% off $50 iTunes gift cards (9to5mac.com)