BV Commerce 5 offers "anonymous" checkout. I'm not sure what to call the feature other than "anonymous." Maybe "guest" checkout is more appropriate because you still collect the name and address of the customers. The feature was designed so that customers were not required to create an account during the checkout process.

Jared M. Spool of User Interface Engineering recently posted an article explaining that making it clear that registration was not required during checkout boosted one of their client's web sales by 300 million dollars. What UIE did was to change the text of a button from "Register" to "Continue" which was seen as less intrusive by shoppers during the checkout process. A simple change that had the effect of making the login step optional.

There are plenty of reasons to require customers to register during checkout. On the BV Software Store we require customers to create an account because we sell electronic goods and have found that when customers explicitly create their own account it is easier for them to remember later. This saves us some support requests about usernames and passwords. Also, our audience tends to be fairly technical and isn't afraid of creating accounts.

If your store requires registration during checkout think carefully about exactly why you require it. You may be losing a significant number of sales because of it.