How Do You Manage Ideas?

I'll be moving early this summer, and so I've started the long process of weeding through papers and possessions. As I went through a stack recently, I came across a folder full of clippings from Fall 2006. Curious, I flipped through it -- and realized it was my last attempt to start an "idea file” where I could always go for inspiration.
Part of being a freelance writer is constantly drumming up new ideas for articles, blog posts and so forth. So I love the idea of building up a bank of leads for the inevitable stretches when my brain is frazzled and unable to piece thoughts together. But given that I didn't look at my idea file for 4.5 years, it clearly wasn't doing me much good during that time. And, indeed, when I flipped through it recently, very few of the articles had much relevance. This blog post is pretty much the only thing they inspired, except for a list of plants that might look nice in a garden if I decide to start one.

So I'd love to hear from someone who's figured out a better process for managing their ideas. How do you build up ideas so you have a ready source of inspiration? Do you keep a file on your computer? A physical file with magazine clippings? A recording of thoughts? Do you review these (and purge these) regularly?

I hope to write about some of the best systems people use in the near future, so please send them along!

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