I have had an amazing experience to customize my own dress by eShakti brand.
As they say: "We design, you customize!" It was pretty much fun and simple. I just choose a custom-styling options on their site and using FX feature to see how picture is changed, clicked on neckline/sleeve/length and here I go - my dress is custom designed how I like and ready for tailoring.
I like this idea, because I was involved myself in creating my own dress and eShakti team did perfect job to create my idea into life.