Portable DAC

Is there a smallish portable DAC out there suitable for travel? I would like a battery powered device to use with my mp3 and IPad. Thank you for your advice.
Furutech just came out with a good one with headphone output. Jeff Dorgay at TONEAudio positively reviewed it.
Centrance Dacport- usb powered
HRT Streamer- usb powered
I am looking for a non USB solution
I have been looking at entry level through high end units and the Furutech Cruise or Stride are appealing. Withan 80 hour battery life, it will outlast the source. I wish there was an alternative to MSRP.
Maybe try one of Ray Samuel's units.