With Web shops set to become a major shopping phenomenon this season it is important to keep in mind how many online shopping days there are left to go. For traditional shoppers there are 23 days left to fill your stockings... not so for online retailing. Because ordering online doesn't mean actually receiving your pressie via your screen on Dec 25, most online retailers are advising their customers to order fast. Great Universal, for example, says shoppers can only buy selected items up to the 21st of this month if they want them delivered on time. Online bookstore, Amazon, reckons it has managed to maximize the amount of shopping time available to Internet users with its online gift certificate, which effectively makes gifts available right up to the last minute - as long as you allow a "number" of days for delivery. Ironically, none of the e-shops ZDNet UK News spoke to could come up with a solution to extending the window for Christmas shopping simply because the vast majority of them rely on that technologically barren institution we all love to loathe... the Post Office.