I think that one of the things that keeps people in technology at the top of their game is a certain willingness to experiment. I don't mean potentially lethal combinations of Mt. Dew and energy drinks, but rather with new technology that they're not already familiar with.
For me, in my career stage, I also think it's critical because I do a lot less hands-on, in-the-weeds work, but I do often work with others to lead them down the path of better software development. In that situation, I think it's important to be able to walk the walk and talk the talk, with a high degree of credibility. For me, that means building real things both in work when the situation allows, and also on my own time.
My brain bandwidth has been pretty thin the last few months, due to some combination of work, buying a house, and a great many other things that add up. The house part has largely been resolved, which has lifted enough psychic weight to let some of that experimentation desire to come back in, and it's amazing what that does for my enthusiasm. If that weren't enough, this is the time of year where all kinds of new and interesting stuff gets announced, especially with Microsoft-related stuff, so that helps too.
What have I been up to? I've been looking at pushing more of my sites to the cloud, I've been messing with Lucene.net (a search engine) for one of my projects, spending more time with client-side frameworks, exploring C# code written for iOS and Android... there is so much to learn and play with right now.
If working in technology isn't fun, you're doing it wrong. At no time in history has there been more opportunity.