Option to decode dolby / dts

I would like to know if there is in the market an option to decode the multichannel audio from movies that is not a proccesor or receiver?, let me explain: I use a small computer to play / store my movies. If I want to decode the audio I need a proccesor, but what I love to have is a small external device - like a dac is for regular audio- that I can run a hdmi cable and from there run rcas to my power amps (hope idea is clear), Any suggestions?
Thanks in advance
NAD has a new D.A.C. Called the M51. It has HDMI inputs and should be able to decode you Dolby signal to stereo but if you want it to decode it in 5.1 or the like then you need a Processor.

To make it simple, to take a digital signal and make it analog you need a Digital to Analog converter.

Both your typical D.A.C. and surround sound processor are both Digital to Analog Converters, the main difference is that a surround sound processor with output analog in 5.1 channels or more and your typical D.A.C. Is just two channels, stereo. You should be able to go into a good surround sound processor and thru the menus speaker selection just turn on the main two channel and that will give you stereo, sort of anyway.
There are inexpensive S/PDIF versions, although they do not have volume control. Can you use those? Finding an HDMI 5.1 converter is harder. If you are not using the lossless codecs, you can buy an old receiver that does 5.1 conversion with pre-outs for not much money, although they are not small.
I am interested in this also. For me it is wanting to convert the 5.1 into 2 channel (PCM?) so i can use my Tascam DAT player as a DAC. I would never, of course, record any Great Performances or Austin City boundries. All I get now is a chatter noise when I go from the cable box to the DAT. Alot of people say there are hidden menus on the cable box but I can't find them. And no, I do not want a surround receiver.
Thanks for the responses; thats what I thought. My idea is to have a small sxternal surround sound processor that can convert the digital audio signal of my movies to analog (Dolby and DTS in all its options)and control the volume with the computer program that Im using to play the video. The intention is not to have a big processor in my system just a small surround processor that just that job and nothing more: no multiple inputs,etc.