Panasonic has a number of budget headphones, including the RP-HX40s, that perform remarkably well for their low price points. The RP-HX40 is an on-ear model that comes in multiple colors and can be picked up for around $20 online. This model's value is enhanced further with an integrated microphone (for making cell phone calls) and inline volume controls.
From a design standpoint, the RP-HX40s are lightweight and relatively attractive. That said, when you pick them up, they do seem like an inexpensive pair of headphones and are essentially all plastic except for the cloth covering on the lightly padded earpieces.
On a positive note those earpieces swivel and fold flat; the headphones, however, do not fold up for more compact storage.
More critically speaking, the cords leading up to the earpieces are pretty thin and the RP-HX40s aren't terribly comfortable. They're not uncomfortable, but they could use a bit of padding on the headband (there's none) and the cloth on the earpads is a little slick, so the headphones have a tendency to slide around a touch on your ears. If, for instance, the cloth had been replaced with some sort of faux leather, that probably wouldn't happen.
Because the fit and finish on these headphones screams "budget," I wasn't expecting them to sound all that good. But once again another pair of inexpensive Panasonic headphones exceeded my expectations on the performance front (they sound much better than the RP-HX35s, which are among the few Panasonics to disappoint).