Ah... Another detail I just noticed (on K3-v3.2.1 image):
The wget installed is the minimum function one supplied by busybox.
Which also means that the info googling "man wget" will not describe this busybox version.
The curl installed is the stand-alone utility.
What google: man curl returns is what you have.
A quick reference with examples:
http://curl.haxx.se/docs/manual.html
Note: The Busybox wget does not do SSL (ftps, https) which you might need, the stand alone curl does (as does the stand alone wget).
And/Or: If your pod-site needs user/password entries, I would plan on using the stand-alone curl over the Busybox stripped down version of wget.
Note 2: cURL utility is built against the libcurl.so library - also installed on the kindle.
You can get ambitious and write code for your podcatcher that uses libcurl.so features.
(-lcurl option on your compile command line)
Note 3: There is a Lua binding for libcurl. The pdf reader being worked on here is controlled by Lua scripting.
So there you go, all the parts you need to code up some background music while using the pdf reader (or to let the pdf reader, "read" a pdf file located on a network).