What keeps me away from Sony's digital camera is the extra memory stick I need to purchase that is only compatible with a Sony. DSC owners, could you please tell us how much a 256 MB or a 512MB memory stick cost you? I fear this may increase the total cost by $100 or more. Also, I'd probably want to buy an extra battery. How much is the battery by itself? Anything else I need to be aware of? I do like the DSC's for their compact design.