It is not often an airline does something special.  But I've noticed significantly better customer service on United Airlines in the last year.  The crew, staff, and operators have all been extremely helpful.  In contrast to some other airlines I fly, I have had a very good experience with United (though I admit you cannot draw conclusions from just my experience).

Case in point:
last week my wife and I took a short thanksgiving vacation to Sydney.  After the long flight from San Francisco to Sydney, tired and bleary, I forgot my Kindle on the plane.  I realized it after we went through security, bummed that I was so stupid to have left it on the plane, but counted it as a lost device and did not bother contacting anyone about it.

Then, a few hours later, I get an email:

Hi Mr. Hoffman

Did you leave a Kindle on board UA 863 when you arrived into Sydney today?
It is locked up in our high value locker.

Let me know if you wish to pick I up before you travel out of Sydney on the 28th November

Regards

Stuart Mann
Airport Operations Supervisor
United Airlines
Sydney

wow.  What great service.   Mr. Mann emailed me directly and, when I got to the airport leaving Sydney back to SFO, the Kindle was waiting for me at the check-in and I was able to enjoy it on the flight home. 

Thank you United Airlines!  Your service is really appreciated!