While the conference content is typically valuable, that's not where I get the most benefit. When a speaker is interesting but not completely engaging (typically good content and poor presentation), I find my mind wondering to my own ideas and plans. Are we planning SOA? Where does Agile fit? What about virtualization? I'll convert what the speaker is saying into my own thoughts, teams and plans. Sometimes it's completely unrelated to the speaker's topic, but triggered by it. I come up with more ideas at conferences than at any other time.
My team gets a lot of spam email from me at conferences, "what about this...". What I am trying to do is engage them in my new thinking. Frankly, a better way to do that is to take them to the conference with you. If you can't do that, then write up your conference notes and share them with your team.
Give yourself a "safe" place away from your day-to-day responsibilities to day-dream about your technology plans.