One of the ways I keep my well of creativity overflowing is through working the zig zag.
I write 5 devotional posts for the Connect Devotional every week. This past week I wrote 5 posts of just 5 verses. Every post needs to contains something slightly insightful and something slightly applicable. I've written over 600 of these posts in the last two years. My well of creativity would be completely exhausted if writing Connect Devotionals was my only creative work.
Ziging and zaging keeps me fresh.
Every week I do some small piece of graphic design. I edit or give feedback on someone else's creative work. I write fiction or poetry or blog posts write here. I write Bible studies for LaFe. I preach, teach, train and speak. Creating in other venues doesn't drain my creative energy. Surprisingly, creativity creates new energy for creativity.
This is the same reason I read theology books as well as fantasy/sci-fi (and business and self-help and history and memoirs and novels and cultural studies). I read old and new books. I read books by men and women and across racial and ethnic lines. This breadth of input keeps me ziging and zaging ... keeps me from getting bored.
Maybe that's the point: boredom kills creativity.