8 Steps to Better Posture
If you're sitting at the computer for more than an hour at a time, you're putting yourself at risk of developing injuries of the hand/arm, shoulder, neck, and back. Obviously these injuries don't occur immediately. They take time to form, due to gradual adaptation of your body to unnatural position. Essentially you're molding your body.
That being said, there are things you can do to counteract any problems from cropping up. Here are a few things that I do, that you could easily incorporate...
1) Strength training the abdominal muscles and lower back muscles.
2) Take a break every 30 minutes. Stand up, walk around, shake your body out and get a glass of water.
3) Stretch the hamstrings (back of the leg) and quadriceps (front of the leg) lightly. Sitting for long periods of time causes some tightness in the legs which can lead to lower back tightness or pain.
4) Take some deep breaths that fill your lower abdomen (stomach). Often while sitting at the computer for long periods of time, people tend to lean forward or slouch, leading to more shallow breaths and reduced oxygen intake.
5) Sit up straight with chin up. If possible, have your screen on level with your eye- line to avoid jutting your head out, leading to stress in the neck and spine.
6) Sit on a Swiss ball (stability ball). I only use it once in a while, but some people swear by it. Sitting on the stability ball forces your body to contract the posture muscles so that you don't fall over. It also strengthens the "core" muscles.
7) Foam roller. I love this thing. I foam- roll my full body twice per day and sometimes more if I'm sitting for long periods of time. Plenty of places online to purchase one for about 10- 20 bucks.
8) Arrange your work station properly. I'm not a work station expert, but you can find a comprehensive information here- Cornell Universities' Ergonomic Guidelines for Arranging a Computer Workstation
Keep in mind, you may have a lean body, but if you've got bad posture, it offsets the entire presentation.

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