We make heavy use of OneNote which probably isn’t much of a surprise, but Tyla and I also use it a lot at home. We both have our own sections where we keep all kinds of notes and then we have a shared section where we keep the grocery list, ideas for gifts for friends and family, lists of doctors, and much more. It’s a great tool for getting rid of miscellaneous pieces of paper and for keeping in sync with other people.
OneNote used to be a paid product but now it’s completely free. You can get it on Windows Phone, Windows, Mac, iPhone and Android. The Office blog has more information and links to download all the freebies.