Linux – Command line tool to identify audio file specs

It may not hit every point on your list, but I use an Apple Airport Express to achieve the same goal.

• Its wireless (and supports security)
• The output is a 1/8 inch stereo jack
• Amazon lists it at $95 dollars currently, so near your price point
• If you have an iPhone or an iPod touch there is a Remote app you can use to control playback (including playlist support)

This solutions obviously needs iTunes as the serving software, but if your server machine is always on then I'd suggest you leave it running on that. This would also get around the Wake from sleep issue.

Update You may be able to use Salling Clicker as the remote on your phone (though I haven't tried it myself). There's a free trial which may be worth a look.

Not perfect, but with the plugin foo_run for foobar2000 you could easily launch a web search with your tags (fb2k is to iTunes what firefox 3.5 is to IE 6...)

So, now that everything is installed, to launch a bm4djs.com search on artist & title with foo_run, add a new service with this path properties (in foobar2000 preferences > tools > run services):

http://www.bpm4djs.com/index.php?app_mode=search&search=true&site=1&sv_artist=$replace(%artist%, ,+)&sv_title=$replace(%title%, ,+)&sv_accuracy=tolerant&sv_genere=4&submit=Go

for album & title:

http://www.bpm4djs.com/index.php?app_mode=search&search=true&site=1&sv_title=$replace(%title%, ,+)&sv_album=$replace(%album%, ,+)&sv_accuracy=tolerant&sv_genere=4&submit=Go

for artist alone:

http://www.bpm4djs.com/index.php?app_mode=search&search=true&site=1&sv_artist=$replace(%artist%, ,+)&sv_accuracy=tolerant&sv_genere=4&submit=Go

for artist & bpm (if your bpm tag name is "BPM"):

http://www.bpm4djs.com/index.php?app_mode=search&search=true&site=1&sv_artist=$replace(%artist%, ,+)sv_bpm=%bpm%&sv_accuracy=tolerant&sv_genere=4&submit=Go

etc...

You could certainly tweak it better with the foobar2000's title formatting and a little study of the search url of bpm4dj or any other website...

And, cherry on the cake, foobar2000 recently got a BPM plugin, it's still in early stage but the dev looks motivated.