Tippr: Get $20 at Overstock.com for $10

Tippr has got a great new National offer today: get $20 at Overstock.com for $10.  Here are the terms:

• Limit per person: 1
• Promotion expires on January 19, 2013.
• Promotional value may only be redeemed through April 21, 2012, by 11:59 PM MST, except where prohibited by law; the cash value does not expire.
• Limit one voucher per person, per transaction.
• Cannot ship to P.O. boxes; certain items cannot be shipped to Alaska and Hawaii.
• This offer applies to U.S. orders only.
• May only be used to purchase goods or services under the "Shopping Tab."
• May not be used to purchase gift cards, cellular telephone plans, or for international orders.
• Offer excludes orders comprising products from Books, Music, Movies, Games, and Electronics categories, as well as items within the Cars, Travel, Insurance, and Gold Redemption categories.
• This promotion cannot be combined with any other offer or coupon.