Advice on trip to Italy/Spain

I am going to be traveling to Rome and then Madrid for a 1.5 week stay. I will be bringing my D50 along with the 18-55 with me. I just bought a Tamrac 5683 Holster bag after reading reviews on here.

My question is regarding memory cards. I don't want to take my laptop since I will be staying in hostels. I currently have 2 1gb cards and was wondering what my best options would be for the trip. Should I buy some 2gb cards (I think that is the most that the D50 can handle), or is there an alternative (some sort of device that I can plug the sd card into that might hold something like 10gb?).

Also, how much memory do you think I might take up? I usually shoot in Large Fine Jpeg (not into RAW processing just yet). I know this is a function of how trigger happy I get, but I just wanted a rough estimate from those of you who travel.

One last thing :), if any of you have recommendations of places that I MUST visit for some good photographic opportunities, go ahead and let me know.

Thanks for all the help,

Miguel
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