I have a good attention span and am not easily distracted by sites like HN, but I've noticed that eye strain is a big problem. Also, like you mentioned, chatter

I have a good attention span and am not easily distracted by sites like HN, but I've noticed that eye strain is a big problem. Also, like you mentioned, chattering coworkers (I've only worn earbuds so far; I need to drag my ATH-M50s to the office) is a big issue. We're in an open floor plan and so I don't get more than maybe 20 minutes of focus at most before people talking near me disturbs me. Maybe it's because of the eye strain difference, but I can sit and read a book for hours upon hours and not have an issue while something about sitting at a desk and staring at a computer makes me want start to fidget and look elsewhere.