Globals, instance variables, and Visual Studio

Just got around to reading Charles Petzold's article on Visual Studio's code-writing aids and found this interesting snippet:

In the pre-object oriented days of C programming, we had local variables and global variables, variables inside of functions, and variables outside of functions. One objective of good programming in C was in keeping the number of global variables to a minimum. Because any global variable could be modified by any function, it was easier to get the sense of a program if there simply weren’t very many of them — if functions communicated among themselves strictly through arguments and return values.

Sometimes, however, C programmers got a little, let’s say, sleepy, and made a lot of variables global that didn’t really need to be, because it was just easier that way. Rather than add an extra argument to a function, why not just store it as a global?

Global variables are basically gone in object-oriented programming, except that fields are now the new global variables, and they can be abused just as badly.

The similarities don't end there: While instance variables are good in general, they're "global" to their class, and can be abused just as well, and can make your class's code just as unreadable. In procedural C programming, you have static variables, which are the same as a global, but can only be accessed from inside the function they were declared in. It'd be nice if there was a similar construct for instance variables, i.e. a per-instance static or so... Or is there a pattern you folks can recommend that beautifully avoids this without a new language construct?

To offer a concrete example, let's take asynchronous mouse-tracking inside a view, where you typically use ivars to keep track of what item is currently highlighted etc. Any alternatives to ivars? Is this actually a Good Thing(tm) ?

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