Project 2 (paper): I made this mini-album out of a set of 6x4" numerical (31) tabbed index cards. I decorated the cover with a vintage book page, some misted paint over a stencil, sewing machine stitching, a punched shape from an old card ("life") and some letter stickers. I used my wire-binder and punch to bind. Not entirely sure how I'll use it yet. One thought is as a perpetual notable dates calendar. On each page I list all the birthdays, anniversaries, etc that fall on that numbered day. No matter what month, I can turn to that page and see if anything is coming up. I have this routine when I am standing in a store where I'll say "OK, it's XXX month, today is XX. What is coming up that I need to remember? Anyone's birthday?" With this, no matter what the month, I can turn to that day (or a day coming up in like a week) and know what's on the horizon.
Another idea was as a one-line journal. Have you seen those? Journals where the intent is to just list one item for each day. The books are fairly small, yet contain 5 years worth of notable comments. I've seen them made in book format and in boxes with index cards. For that use, you could either write directly on the tabbed cards (always writing on the appropriately numbered day no matter what month) or write on index cards and add them to the book behind the correct tab by pulling apart and reclosing the binding.