Well, I haven't been yet, but I have plans.

I'm going to sew DD a Minnie Mouse dress
(red polka-dotted). I've bought fabric to make me a utility skirt, with heaps and heaps of pockets so I don't need to take a bag into the park; I'm hoping to make DD a little matching one as well. I've bought fabric and a pattern to make a lovely retro dress, which will be terribly impractical to take on holiday because it requires a tulle petticoat, which will take up half a suitcase. And it's totally wrong for the weather. And I'm pretty sure a retro-type skirt and tulle petticoat is the least practical thing one could possibly wear in
Disneyland.

Still, I might bring it anyway and wear it on a non-Disneyland day, when we're shopping or something. Oh, and I have vague plans to make a fancy outfit to wear for our special dinner at the Napa Rose/Blue Bayou (and also at Medieval Times, and possibly when we go see Wicked!).
In general I want to make a bunch of bright, cheerful, holidayish clothes. I usually tend towards drab and neutral colours, but I want some things that seem festive. And it's always fun to make clothes for DD - toddlers look cute in everything! I have some spring-coloured fabric saved up for the occasion - I want to make everything now while I'm keen, but I don't know how much she'll grow...