Nowadays I find myself in a position which I never thought I'd be in. I haven't touched Delphi for months and struggle to even remember how to write the simplest statements in the language. I feel so guilty about this that I double–click the Delphi shortcut once in a while, sort of like taking a neglected old pet for a walk. And then I realise that I haven't got anything that I want to write—or more accurately, anything that I have time to write properly—and close Delphi down again.
It's not even as if anything has supplanted my Delphi. All that's changed is that I'm now employed professionally as a programmer and I find that I don't want to spend the evening programming after a day at the coal face with J2EE. I spent a year using Visual Basic 6.0 at work and now that we've switched to Java I find that the same thing is happening again and that my VB knowledge is evaporating (some might claim that's a good thing)! All of which proves that languages are like muscle: use them or lose them.