I've definitely had experiences.
Charlie was my first cat. When I was two, this ginger kitty kept showing up at our house and my dad would chase him with a broom. Punk. One day when my dad was at work, my mom watched this same cat walk into our house from the back patio (we were all outside playing - my mom did daycare). She followed him as he checked out every single room. By the time he came to my room in the back, he settled for this room and umped onto my bed and and fell asleep. By the time my dad came home, he was still on the bed. My mom showed my dad and he knew he was defeated. "Well...looks like we got another cat..."
Charlie got back to my dad by peeing on him TWICE! He NEVER did that to anyone except my dad, ROFL! "That's what you get for scaring me with that broom!" Typical feisty red-head.
I had him for 17 wonderful years. The last year was hard. He lost a lot of weight but he was happy. We all knew it was getting close for him when he never left my bedroom. Just before I got home from work, Charlie walked into my parents' bedroom. My dad picked him up and after a small meow, he passed away in my dad's arms. It was very peaceful and there was no sign of any physical pain from him. Even though I wasn't there, I'm glad he wasn't alone.
The hallway to my bedroom has hardwood flooring. As Charlie had aged, one of his claws couldn't retract back so you could always hear it scraping the floor as he walked to my room. It never got caught on anything (it wasn't that far out) and we kept it trimmed. It was cute because I could always here him walking to me.
Up until I moved out of my folks' home, I would frequently hear that scrape getting closer to my room. And on numerous occasions I would feel the bed dip as if he jumped on it both while I was awake (and not falling asleep) and being woken up from it. It always broke my heart because I missed him so much, but was thrilled that he was still with me.
The two cats my folks had before I was born were feral kittens that were born on the side of their house when they first moved in. Long story short, they never were fully domesticated and one took off after we got a dog 7 years later. The other one, Trouble, stuck around.
After Trouble had been put to sleep, I've actually seen her numerous times in the house. I believe in spirits and the unknown so it surprised me at first (this was before Charlie had passed) but it wasn't scary. She was always in the same spot and it would always be of her back and tail that I would see. The hallway bathroom shares a wall with the kitchen, and I would always see her in between the two rooms in the hallway.
Years later, I told my mom that I had seen Trouble on numerous occasions. She went quiet, asked if it was in the hallway between the bathroom and kitchen, which surprised me. My dad, who doesn't believe in anything supernatural or unknown, had claimed to have seen her a few times before. In the same spot. I was floored. Trouble was "his" cat.
Our first dog, Jacques, was a Bichon that we rescued. Near the end, he had really bad cushings and was never full. Our other dog Xillia would have to be fed in my room or else he would eat her food too. So, again, I could hear Jacques coming down the hallway to eat Xillia's food from my room, the stinker, lol. A few days after we had to put him to sleep, I heard him huffing down the hallway and without thinking, yelled at him to leave Xillia alone. Immediately after I had said that, I realized that it couldn't have been hime so I peaked my head out the hallway and he wasn't there. I felt horrible because he could have been coming to visit and I just yelled at him. It could have been residual though, because that was the only time I heard him.
Even though they're no longer physically with you, knowing that you are still loved even after their passing leaves me at peace. My folks say that they don't see Trouble anymore, and I don't get the feeling that Charlie is there either. I hope that they have moved on to another birth and to another family that will love them as much as we have.