Just had a look on Tesco's website - http://www.tesco.com/help/page.asp?choiceA=elec&choiceB=5&choicec=5&page=sharAns26.htm - I can't quite decide whether this means they just leave items on the doorstep (not really a good idea in London) or if they leave a card and you then have to arrange for delivery at a later date - IME when I've done things like this in the past they'll only offer 'morning' or 'afternoon' as the alternatives and only deliver during the week. I can't really afford to take time off work to have things delivered to me.