Personally, I'd always recommend a business notebook, even a budget one. I got a second hand HP NX7300 a couple of years ago (manufactured in 2007) with a T7200 PDC processor and 1 GB RAM coupled with a 120 GB HDD for around $100.
Still runs like a champ for everything I throw at it (movies, heavy browsing, documents etc). Granted, my use isn't very taxing on the processor, but it has been on for around 18 hours every day for its entire life. Upgraded the RAM to 4 GB DDR2, 500 GB HDD. Fallen multiple times, people have sat on it and it even fell off a bike once. Very few scratches and the matte display is a breeze.
Anyway, that's me rambling. I know quite a few people who bought refurbished or new business laptops and they've always held up brilliantly. Dell Latitudes, Probooks, Elitebooks, NX series laptops, Lenovo Thinkpads, Lenovo's B line of business laptops - they're all long lasting. If you need power, opt for a decent new business laptop. You won't regret it.