https://wishy.gift/ - a wishlist web app that we launched a bit too close to Christmas to be of use to anyone. We got just about 90 users at the moment, and have gotten lots of good feedback and feature requests.

Friends and family I've talked to found it really useful for the Christmas shopping, and my SO showed me the wishlist of a friend of hers - which had loads of items added to it - and almost every single item was checked off.

There's some stuff we're going to add, but our main issue is finding out how to market it, and explain the service in a good way.