I have a set of Sennheiser HD555. Though arguably not 'audiophile' quality, a good value with tremendous sound. They are a so-called open ear design so realize that others around you will hear the bleed through. Above all else, extremely comfortable to wear! The cup seal is suede in nature and minimizes prespiration around the periphery. I would describe the sound as 'warm'.
On the earbud front, I have a set of Etymotic ER-6s. For places where I don't want to advertise that I'm wearing headphones or simply need the compactness, they're amazingly good for such a small package. Be prepared that in exchange for their noise blocking properties, they're like wearing foam ear plugs, as in the 'I'm running a chainsaw' sense. Simply put, they can be uncomfortable in the long haul. Still, quite amazing for such a small package.