I have over the years mastered the basic functionality of sets of visual studio (1995-2000), forte/netbeans (2000-2003) and Eclipse (2005-current).
As with any everyday user, I have fallen in love with Eclipse and can't even remember how to work in previously favorite IDE's.
For most of 2008 I served in the prestigious position of Product Manager for MyEclipse, the superb IDE based on the Eclipse platform. I still use MyEclipse everyday, and regard it as one of the finest accomplishments of tooling vendors anywhere - as the perfect merger of open source tooling and proprietary development and support.
I have also created several successful plugins with Eclipse. See tools.