I only have three things of my own that I have kept for myself. One was a pouch I made quite some time ago, and it wasn't until I was completely done with it that I realized that I didn't catch the fabric completely in the seam along the zipper. I caught it enough to hold together, but it frayed a little bit -- so I kept that..
Secondly, last August, I decided to finally make a bag for myself. I needed a bag that worked nicely for things I need to carry every day to school (I'm an instructor, so I needed specific pockets for graded papers, pens, calculator, etc). It's the only item that I've ever actually picked out and purchased fabric specifically for and sat down and put together the pattern for myself, knowing I was going to keep it. I am still very happy with that bag and use it every day :) It serves its purpose of having a pocket for everything, and when people ask what else I do or the subject comes up, I just show them the bag.
Finally, I have a monogrammed keychain I started selling, and I wanted to take a picture of it but couldn't think of anyone off the top of my head to make one for, so I made the letter K and kept it. It's on my key ring and holds my business cards.