One of the beauties of the Hipster PDA (which I've been using religiously for months now) is that it offers an extremely portable note taking system. For writers, especially those who are always on the look out for article ideas, this thought capture is essential.
Here's a wonderful video about a man who writes/designs crossword puzzles. I love everything he has to say, so just watch the clip.
Another thing I use, which I'll elaborate on later, is an "Open Jotter" document on my computer. It's an ongoing file of anything that floats into my mind. Whatever I'm doing, I can quickly jot it down, and get back to whatever I'm working on, secure in the fact that my brilliance (or lack thereof) is recorded to return to at a later time.