SUroot, perhaps you could add some information and clarification.
For example, when
I read "portable audio streamer" what comes to mind is a server process (like
Icecast) that can be compiled on a variety of platforms. Something tells me that's not what you meant.
You wrote that you "want something small, cheap with built in stereo speakers. Much in the Guise of a Ghetto blaster", which seems to indicate that you're looking for something that plays music, using your home network as a source. I don't know of any such devices, but if you have an old "ghetto blaster" with a working FM radio, you can get your own home FM radio station, and use the FM radio band to send your signal to any FM radio, without anything extra required. Just Google "home FM transmitter".
Most streaming audio receivers that I've seen, such as the Roku and Squeezebox tend to be more like permanent stereo components. If you're handy with tools and wood and/or metal working, you could cobble together a portable Wi-Fi streaming music player out of these component parts.
For example I have an old Roku audio device with Wi-Fi that I've used to feed its Toslink audio out into the Toslink audio in of a pair of powered speakers. You could build something like that as long as you have an AC power source. It may take a bit more work to make it battery powered.