I have 3 that come to mind right away...
On our trip in March 2013 I was standing in line at the hat store at the end of Main Street with a pair of Mickey ears when a cast member approached me and asked if I was planning on having a name embroidered on it. When I responded that I was she started up a conversation with me asking my name, where I was from, etc. She continued talking to me until we reached the counter and she let the cm behind the counter know that she was making some magic. My name was embroidered on the ears for free! She then gave me a card to commemorate the moment with my name and date on it.
On another trip in November 2013 we were eating dinner at the Garden Grill in EPCOT and my younger sister was about 7 at the time and was really tired and not all that interested in eating. Our waiter, Cory noticed she wasn't really eating and seemed tired and offered to see if he could find her a popsicle in the back. Before he left he let her know he wasn't entirely sure he would be able to find one but he would try. He went off to look and I noticed him walking back towards our table empty handed so I told my sister to not be upset but he didn't have the popsicle, which she was fine with. He then came back to talk to my sister and apologized for not being able to find a popsicle for her. He very easily could have left it at that but instead he said to her "I couldn't find one but I thought you might like this instead" and he handed her a paper Disney cup and smiled. My sister was pretty confused but looked inside and it was an entire cup FULL of Mickey sprinkles. She was so excited and talked about them the entire trip, she emptied the cup into a sandwich bag and carried it with her to the parks for the rest of the trip and ate them while we were in lines. It's been almost 3 years and this memory is still one of my favourite Disney memories. I usually have a hard time remembering cm names but Cory's has stuck in my head because of what he did.
Also on our November 2013 we were celebrating my sweet 16. I ended up sick for the last 2 days of the trip. I stayed in the room the first night alone while the rest of my family went to dinner at Akershus. When they came back my dad took out his phone and showed me a video from the restaurant. My parents had told Ariel I was back at the room and Ariel asked my dad if he had one of those Shellphones and he said yes and she said oo oo can you make it so I can say something to her so he recorded a video of Ariel saying she wished I could be there and I hope to see you soon. She also said how much she loved my bag because I had a backpack that I was getting signed by the characters that trip that my family had taken to the restaurant to get signed for me. We've kept the video and now have it saved!