I don't think there is an easy, cookie-cutter answer that applies across the board, but I do believe the first commandment can help: "You shall have no other gods before me." (Exodus 20:3). A god is something you are devoted to. It is something you give your time, energy, thoughts, and money to. A good way to find out if your hobby has become an idol is to see where your greatest devotion lies. For example, something is wrong when you can name every "smartphone" on every telephone carrier, but you can't name all of the books in the Bible. Something is wrong if you've memorized every batting average in the MLB but don't know Proverbs 3:5-6 by heart. Something is wrong when you know every Star Wars character, but don't know who Nehemiah or Zephaniah is. Something is wrong if you run to your email or facebook rather than your Bible when you first wake up in the morning. Something is wrong when you've learned how to speak Star Trek language and not Biblical Greek and Hebrew! (Yes, people know how to speak Star Trek, Star Wars, and Lord of the Rings languages!) Something is wrong when you spend more time working on your classic car than you do serving the Church of God. Where is your devotion? What do you spend the most time thinking about and meditating on? Is it the God of the universe? Or something else?
For me, God was convicting me that technology was becoming an idol to me. It was competing with Him for the throne of my heart. He told me to shatter my idol. "But God...it's useful!"..."But God...it's fun!"..."But God..." Shatter it. I know that when God calls me to give something up it is for my greatest good and deepest joy. I need to trust Him and give it up. So I'm trying. I've put a "time-limit plug in" on my web browser that limits the time I can spend on useless sites like Facebook and Google Reader. I've deleted all my RSS feeds about technology and have added new feeds about God, Christianity and ministry. I've tried to stick with a rule that says "before you touch anything electronic, you should first touch the Bible." I no longer want to be consumed by my consuming. I want to live a life with purpose and meaning. It's hard to break old habits, but I'm excited to see how much more I can accomplish for the Lord and learn about Him by freeing up all of this "wasted" time. I'm excited to have more time to have meaningful conversations with my wife. I'm excited for more effective ministry. It's going to be a good year. Pray for me.
"Only one life, and gone so fast. Only what's done for Christ will last."