I'm in Canada and have been saving gift cards for about 3 years. When people I know are crossing the border I bug them to bring me back a gift card. I'm on one survey site that actually offers US Disney gift cards so I order them when I hit $100. So my gift cards were all $25, $50, and $100 ones. Oh, and a couple of $10 for some reason.
It was only last week I heard about Disneygiftcard.com. Until then I stored them in a separate wallet I kept hidden in the house, but always had the numbers & security code saved on an Excel spreadsheet with their balances. I'm so glad I found the thread about combining cards! I was worried about paying for the WOC dessert party, meals and especially my park tickets on multiple gift cards!!
So now I have them combined into 5 gift cards. I could have put more $ on and ended up with less cards, but my husband suggested spreading them out more just in case I lose a card while in California. I'll still take photos of the card numbers as I understand Disney will cancel a lost/stolen card and give me a new one, but this feels safer to me.