I've been a developer for over 30 years in one form or another. I learnt Pascal at University and my first job was programming in Fortran 66. I've since moved to C# & .NET via Ada, C and C++.
Over the years I've used most operating systems (apart from MacOS), starting with PR1MOS and then moving onto various flavours of Unix. I'm now exclusively on Windows, but thinking of getting into iPhone/iPod touch/iPad development (if only I could afford a MacBook Pro!).