This sounds really familiar. Like... someone else did this same thing about three or four years ago, based on the same sort of need. Am I just imagining things, or is this an old post?
Philippe - sounds like a neat idea. I wish you lot of luck.
I love the UI, it's clean and very intuitive.
I personally didn't like how the pricing page is going over the website itself as you scroll down.
Edit: wow, I managed to find it. It was right here on HN: http://news.ycombinator.com/item?id=2222522