I've got a few.
I was not feeling well for most of my WDW trip this past May. I spent about 2 hours lying in MK first aid with 2 of my friends who were with me. The CMs were super nice, but the best part was getting a visit from Mickey.

Also, two different times I sat on the floor of a shop and a CM offered to get me a drink of water when we mentioned I wasn't feeling well.
One of my fav stories is the time I was in the Exposition Hall in MK singing to myself as I often do. I was singing "Some day My Prince will Come." Dopey overheard and wanted me to sing the whole thing. Next thing I know, I have about 3 or 4 dwarves listening to me as if I were Snow White in the film! Dopey even sat down and swayed. Then he took my hand and pulled me over to Snow White and the prince and had me sing it again for them! Even the guests applauded and the character greeter cm asked if I was a professional singer!
Here's a twist- guests can create magic for CMs too! I was on the college program in 2001 and often it was the guests who made my day.
One day, I had been giving out mickey stickers to kids. We were just about to close and I was sitting on the floor straightening jewelery when one little girl I had given a sticker to earlier came over to me, said bye, and gave me a hug!
Once I was working the Buzz Lightyear cart during e-ride night and it was sooo slow. Then these 2 girls, about 10 and 4, and their mother were looking at stuff on the cart and started chatting with me. The girls were sooo funny! The older one took one of the woody dolls, put him on her shoulder, and started singing "Mr. Woody on my shoulder!" The little one performed some cute songs for me that she'd learned at school. As they left, the mother thanked me for putting up with them, but I told her I had really enjoyed their company.
I loved chatting with guests who were waiting for people on Space Mountain or Alien Encounter. Once I had a lady tell me she could talk to me all day. Another time, I cheered up a little boy who was upset that he was too short to ride Space Mt. Soon he was happily chatting about everything he had done that day. The mother even took a picture of me with him. hehehe.