Valleywag has learned that Amazon.com has invested $4 million in sale-a-day e-commerce site Woot. The deal gives Amazon right of first refusal to buy the company should Woot hit certain unnamed sales targets, want to go public, or sell to another company. For the most part, the companies operate independently. But there's more to Woot, and its ties to Amazon, than meets the eye.

The company has an extensive back-end sales and distribution network, buying and selling closeout goods to other companies in the industry, including finding items for Amazon to sell on its Gold Box promotion site. It's expanding into T-shirts and wine, as well. Its fulfillment operations are large and sophisticated enough to qualify for FedEx and USPS's SmartPost service (though plenty of users have complained about missed SmartPost deliveries, so that's nothing to brag about). Perhaps the most astounding tidbit of information we got? Woot gets 250,000 views in the first three minutes after midnight from consumers looking to grab the next new item for sale.