Christmas Day may be over for some shoppers, but for others, the post-season rush is an even bigger opportunity than the holiday itself, with huge sales and amazing deals at big retailers as Walmart, Costco and Old Navy and at pharmacy chains like CVS.

Before you begin your pre-New Year's shopping, however, take a moment to go through this list of some of the best post-holiday deals this winter. In the days following Christmas, smart shoppers are able to score everything from nice clothes and fancy jewelry to high-end electronics and bulk Christmas candy.

From Lowes to Walmart, from Costco to Old Navy, here are some of the biggest after Christmas sales of 2011.

Costco: Almost everything in the megastore is selling at 50 to 80 percent off, with cameras and computers up to $250 below the marked price and sports and fitness equipment running up to $1,500 off. Costco club member can also get post-holiday gift baskets, jewelry and even furniture for between $50 and up to thousands in sales.

Old Navy: All holiday items went to the clearance section on Dec. 26, with huge sales on almost everything in the store and free shipping for purchases over $50. Items bought online are up to 50 percent off, but in-store purchases can save you 75 percent off the original price.

Lowes: The home improvement store is offering 50 percent Christmas sales on many post-holiday items, though it takes a bit of digging to uncover the web site's biggest sales.

Walmart: The store's web site offers free shipping on hundreds of thousands of items after the Christmas rush. Sales range everywhere from 30 to 70 percent off, and in-store grabs are likely to be even better. Some of the best tech sales include an Apple iPad 2, 32GB with WiFi at $599 and tablet computers for only $99.

Bloomingdales and Macy's: The sister stores are planning to get rid of a lot of after Christmas merchandise, with sales of 50 to 75 percent off holiday items that encompass everything from handbags and expensive perfume to children's clothing and women's accessories.

Best Buy: The tech store's after Christmas sale runs through today, so shoppers looking to score a great deal online should hurry to the nearest computer for free shipping and big sales. Sales items are everywhere from 5 to almost 75 percent off, and free store pickup is also offered. Some of the best deals? Cameras and camcorders for $300 below the list price, and unlocked smartphones for as low as $39.99.

JCPenney: In anticipation of New Year's sales, JCPenney has announced a Red Zone Clearance on almost everything in stock. The store is offering 70 percent off stocking stuffers, 50 percent off of iPod accessories, and up to 75 percent off of other post-holiday items.

CVS: The pharmacy is making good on after Christmas cravings for more junk food. Most stores are offering sales on chocolates and other Christmas candies at around a 50 percent markdown.

Dollar General: Up to 50 percent off of everything in the store as part of its 2011 after Christmas sale, which will save frugal customers even more than usual.

J. Crew: Until Dec. 31, pretty much everything in the store is around 80 percent off. Ring in the New Year this post-holiday season with some great sales on fall merchandise here.

Target: Target's biggest sales were yesterday, Dec. 26, but the popular store is still offering big deals to post-holiday shoppers. Online buys are up to 65 percent off, and there are thousands of last-chance deals being offered only in stores. In-store returns are also offered, in case your Christmas gifts didn't go over as well as you planned.

Sam's Club: This Costco alternative is launching a New Year's sale that includes a Dell Inspiron 14R laptop and diamond pendant in 14K white gold for under $300, as well as numerous bulk food items with big sales prices.