Amazon has the newer model Sennheiser HD 559 for $85. These are OPEN back. Sound will leak. Most places are selling these for $150. These are the newer model of HD 558 which have gone many times on Frontpage when at $70.
For $15 more its worth an upgrade. I do not know if the new model allows you to do the foam mod which people claim make them sound more like HD 598/HD 599 model.
Also note that these do not come with the small traditional headphones plug. Only comes with 6.3 mm straight, gold-plated plug. Which is a shame because at this price point Sennheiser should include one.