[azrussell132]

My two favorites are the Pioneer SE-A1000 and the Panasonic RP-HTF600's.  

 

[serman005]

They aren't truly giant killers, because the giants are not threatened by them, but my Superlux 681 Evo's do sound remarkably good for the money. Much, much, much better than my HD202's, for a similar price. I have spent much more on headphones, but I continue to be amazed by Takstar, Superlux, Monoprice, and others and at how they are able to deliver such value for such reasonable pricing. It is amazing to me. To me, the law of diminishing returns is alive and well in the headphone business... Just one man's opinion.

 

[zazex]

The Yamaha HPH-200's hit it out of the park IMO.
I'm continually amazed by these light, comfortable,
great sounding headphones.  Paid about $80.00
for them about a year ago.

 

[JoeDoe]

I'll jump in here:
 
1. KSC-75: with the headband and Kramer mod, these get up in the $100 range. 
 
2. SennGrado: Grado headband assembly + cups + PX100 drivers = $300-400 worth of sound.
 
3. Baldoor E100 Earbell: $14 price tag. $80-100 sound. 

 

[Toom]

Earbell E100 - makes me sad I have wasted so much money on inferior IEMs these last few years. For a tenner, these little earbud things are insane.

 

[bbieringer]

Philips SHP9500. Have been seen going for $50 these past few months.
 
I feel that they compete with an amped HD600

 

[Arsis]

TTPOD T1E, Brainwavz S0 and Sennheiser HD439. I love budget-fi. I'd much rather have variety than one expensive set.

 

[HumbleMan]

I decided to sell my HD650, K701, PS1000, and 325i after realizing I got the same sound, more or less, from my SR850 and HD668B. I still don't understand it.

 

[chimney189]

I'd love if this thread was more active.
I have a feeling that one day I'll just sell my expensive headphones and get into the habit of buying headphones that are at least half the price, if not more.