This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
I believe that passing it (or the object it exists in) as a parameter is the only way to do so. An instance variable exists in an object, and there might be multiple objects of the same class, the static method will never know what to use, hence it's not allowed in the language, and it will not compile if you try to access an instance variable (or invoke an instance method) from a static method. (this applies to Java as well)