I currently have over 1100 recipes in a Recipes notebook, with tags for categories (maindish, side, appetizer, condiment, etc.), as well as for whether or not they are "meat" or "veg" (I'm vegetarian, hubby is not). Some recipes are tagged with both "meat" and "veg" if they can be adapted either way. I also have tags for "reference" as someone else mentioned above, for equivalencies, measurements, charts, tips, etc. Tags for "holiday" and "gift" also come in handy this time of year when I'm baking a lot for neighbors and co-workers. I clip a lot from the web, and hubby and I also scanned and dumped the hundreds and hundreds of pieces of paper I'd collected over the years, from hand-written recipes, those I'd printed from the web or torn out of magazines. In hindsight, I should have maybe created two notebooks, one for cooking and one for baking, although searching for tags makes it easy to find what I need. I also add my own comments to each recipe, and copy/paste website comments that are helpful when clipping from the internet. One tag set I wish I had used early on is "weekday" or "quick," to find things to make after a long day at work. One thing I need to figure out is a quick way to eliminate duplicates. I've found a few while looking for specific recipes, but I guess I had multiple print-outs of some recipes in my stacks.