I like a bargain, and I like headphones. I once made a joke with my wife that everytime she buys a pair of shoes, I get to buy a pair of headphones.  I currently own two Beyerdynamic DT770-pros, a tattered Sony MDR-V6, AKG 240M's, Koss PortaPro's, Sennheiser PX100's, Sennheiser HD201's, and custom molded IEM's (in hear monitors). 

Bargains that impress me with great sound quality:

Sennheiser HD201- Available for under $20 from Amazon, I find these comfortable with really good fidelity.  Featuring a circumaural, sealed design, they reduce outside noise, create minimal bleed into a mic, and don't press on my pinna, which can really hurt after awhile.  They aren't very bass heavy, but for monitoring voice-over recordings that is a good thing.  They don't get terribly loud with an iPod, but I am far from deaf so that's fine, too. 

Sennheiser PX100- While they look like your classic cheap "walkman" headphones, looks are deceiving.  These $50 beauties (or less) sound shockingly great.  They come folded in a nice hardcase with wire caddy to keep everything well protected in your laptop bag.  They are soon to be replaced by the PX100-II's, so you might find some deals.  Then again, they were so well loved it could be hard to even find them for sale at all.

Koss PortaPro- Koss is unique in the business with a lifetime warranty on all of their headphones, and these you'll want to keep around for a long time.  With sound very similar to the PX100's, and a unique headband with adjustments for the amount of tension on the earpads, the Porta Pro has stood the test of time.  They fold down pretty small and slip into a small satchel.  They sell for $50 on the Koss website and can be found for much less.  Get spare ear pads for them if you use them a lot, they eventually fall apart. 

Have a pair of headphones you just can't live without?  Leave a comment and share!