I think that the most fulfilling part of aviation for me is the constant challenge and development.
There is always something to learn, and with technology developing at such a rate, there are always new things to find out about.
The people are also second to none. They are, generally, friendly, helpful people who always have time for each other.
Thank you to everyone.
Oh and not forgetting, the challenge of having to deal with irate pilots like EESDL, who just want their helicopters!!!!