Absolutely - the most recent I can remember is with my cell phone carrier (Sprint). My scary old job required I make a LOT of phone calls. The company I worked for was to provide a phone, but the one they gave me didn't work. In the month it took to get repaired, they told me to use my phone. I did and ended up with over $400 in overages. When I asked to be refunded, they said because they didn't have anything written that they told me to use the phone (they didn't they told me verbally).
I called Sprint, explained what happened, and they let me pay on the bill for over 4 months, with no cut or change in service. I've never heard of a cell carrier letting you carry a balance THAT long, but they did with no problem. When I made my last payment, I called the customer service, and just thanked the guy who answered. He was pretty shocked and happy
I now work with a customer service based company, and I do make and receive a LOT of phone calls. It's my priority for myself to give exceptional phone service - no um and ahing, no long blank pauses, and I research each case before I call, so I can have all the answers and possible fixes I can find (I now deal primarily with cases that have had a failure of service, so it's my job to "fix" our mistake AND fix our relationship with the client). I often get a sincere thank you, and every time it makes me feel good and that much more motivated to help the next client.

I've also received emails from management when a client has contacted our company to say I gave them great care, and I tell you, that is a WONDERFUL feeling to have management forward that to me, even if it is a "Jennifer L. did a great job helping me with my case."
It's kinda neat to see from a company standpoint how effect phone skills can help a situation (and yes, we have to take "Effective Phone Skills" classes and trainings :D )