Receiver for headphone use only

$100 sounds optomistic, but many report that the Fisher 400 series has a very good headphone section. check head-fi.org.

I use a Marantz CD-5001 CD player in the same configuration (on the night stand) and it works quite well. I paid just over $200 for mine and it was a new open box sale, you might find one used for less. It has a separate headphone amp section and I am very happy with it. I listen through a pair of modded Senn 580s and it has plenty of power for them.

Get a Marantz 2230, 2245 or similiar, built in Japan, early 70's. Have it modded or rebuilt, or with patience wait for a cleaned-up rebuilt one to appear on ebay. For the 2230, which is all you'll need for headphones, the price for a really good one should be below $350 or so.

What about wireless head phones, do these perform well?