Once you're doing that adult thing, you'll start to acquire important documents that you need to keep and have access to. Organization is key to doing this successfully and conveniently. But who says organization can't have some style to it?
You've probably seen other posts touting organizational binders. I did the binder thing for a while when I was in school, but eventually I found that binders didn't cut it for me. They became too bulky and too much to have them satisfactorily sorted to find easy.
Luckily, I found an easy way to store files where they can be useful again, not to mention, much more visually appealing than a traditional filing cabinet.
I use a storage trunk I originally bought for college. I got it from Walmart for a reasonable price. It's lasted through 8 move in/outs and it locks if you want.
Then I added a hanging filing frame from Target. It's only a couple of bucks and you can adjust the length.
I kept mine at full length, but that's way more than I'll need for a long time. Right now I have only half of it with files and most of those are empty. This leaves plenty of room for blankets, which is what I was using it for before this project.
Some ideas of filing categories.
Taxes - W2s, Tax Returns, etc. - you definitely need to keep these
Bank - account information, correspondence, etc.
Loans - statements, interest information
Insurance - copies of policies, correspondence
Utilities - statements
Automobile - your maintenance reports, oil changes, etc.
Health
Retirement
Receipts
User Manuals
Anything else you want
Finally, I added some corkboard to the inside of the lid. I've considered mod-podging some newspaper or decorative paper to the interior, but I did the cork on top for possible functionality. I got a roll of cork with adhesive backing from Amazon. You can also find rolls at craft stores or use those square cork boards they sell in the office section.
Overall it was super simple and cheap to make. You don't have to go crazy like some other posts I've seen, but you can go further than I did too. Make it your own, after all, these are more like guidelines anyway.