News-uploaders
 
The most newsreaders can also be used as uploaders, that is the case with Forte Agent, (and of cource Outlook Express), but if you want to encode with yEnc, then the free versions don't works.

You can try a Google-search for uploaders for the UseNet, and probably get a lot of hits, but as the newsreader, I prefere the uploader from www.cosmicwolf.com: PowerPost2000.

Now some people have made some more development of that uploader, so you are able to upload 4 files at same time, if your news-server allows it, and you upload connection can handle it:

PowerPost-A&A webpage
 
The advantages with PowerPost is, you are able to just repost some single segments, if they are missing.