My cat followed my roommate home last winter. It was snowing pretty hard outside, so we decided to let her sleep in our old apartment for the night until we found her owner. We put posters up all over town, and we even called a few phone numbers we found on different fliers (even though the cats looked different). No one ever called us, so we decided to let her stay a little longer. She was so well behaved and friendly, and we quickly grew attached to her.
We later found out that she was a feral cat who was caught and released. Part of her left ear is missing, which I learned was from ear tipping. This lets people know the cat has been fixed and released back into the wild. It's odd, though, that she was a stray because she adores people and can be quite the attention hog! I'm glad she found us, though, because she's a sweet cat.