Amazon.com (NASDAQ: AMZN) has always been at the forefront of making purchasing from its ubiquitous website as easy as possible. From the early days of one-click shopping, the retailer has made the process of buying merchandise super easy.

Well, it just got easier for those who want to purchase products but have no desire to pay for them immediately.

The world's largest e-tailer signed an agreement with Bill Me Later Inc. to let customers purchase products and be billed for them at a later date. In an interesting twist, Amazon.com also purchased an equity stake in Bill Me Later as well, although the size of the stake is not known.

With the enormous reach of Amazon.com has, is this payment alternative needed? From an economic standpoint, yes. Any payment avenue Amazon.com offers just makes it that much easier to increase sales to a contingent of customers who want a huge array of payment options (for better or worse). The Bill Me Later deal is expected to close in the first quarter of 2008 and should be available as a payment option at Amazon.com shortly thereafter.