I have ergonomized my work environment, and it didn't cost me a fortune. Ergonomics consultant Carol Nicholson (206-383-3740) came to my house, watched me work, got out her tape measure, took photos, and told me what to change.
The big, but simple adjustments were where my monitors sat, and how high I sat. I have a dual monitor system, and I have them to the left and right of the center of my desk. Carol made me choose one as the main monitor, and centered that one in my line of sight. She moved it a lot closer to me, and lowered it.
Then she raised my chair to the point where I needed to remove the pencil drawer of my desk, and found a couple of 3-ring binders for me to use as footrests. My keyboard is now practically in my stomach. She wants me to get a mini-Mac keyboard, one without a number pad, so that my mouse will sit closer to the keyboard. The only other immediate things she wants me to get is a soft gel wrist rest for the keyboard, and a footrest. She has a recommendation for a chair (an RFM Internet chair, model 4834, without armrests), but says I can wait and see how these changes work before committing to that expense.
I just worked for two days processing the files from the Stanford University shoot using this new setup, and survived the effort just fine.