Curiously enough, there are "binaries" newsgroups which allow the posting of text-encoded Binary files. As one might expect, the storage requirement for these newsgroups is enormous. Your ISP generally provides access to usenet... and the better ISP's have a reasonable selection of Binaries newsgroups.

Alternatively, you need to sign up with a commercial newsgroup provider. The advantage is you often have a larger selection and less "missing" parts.

Note: Many of these tools are Command-Line only.

Obviously, you need a newsreader that supports Binary downloads. This is your own preference. See Versiontracker for usenet utilities. I use Thoth as it handles binaries pretty well and is OS X native.

Multi-part posts are often posted as "RAR" files. These files are designated by a series of files that look like this: filename.rar, filename.r01, filename.r02 etc... The unrar utility allows you to decompress these archives and recreate the original files.

Update: There is a new version of WinRar (Beta 3.0) which introduced a new RAR format.

New: Mac OS X Unrar 3.0

Frequently, due to the frequent turnover in newsgroups as well as corrupt posts, there is often a need for reposting these lost and corrupt files.

'par' was developed as a partial solution for this. Special 'par' files (.par, .p01, p02 etc...) are posted along with the RAR files. For each PAR file you have, you will be able to recreate one of the RAR files that you may be missing.

Download it from Sourceforge.

A GUI version is available here.

Reprinted from a Usenet post:
I compiled cdrdao for Mac OS X. This can burn bin/cue files very easily. The only cue/bin pair which haven't worked for me thus far had spaces and hyphens in the filename. Changing the filename and editing the cue file to reflect that solved the problem.

You can download my binary from here:

http://homepage.mac.com/anarkhos/.Pictures/cdrdao.tgz

The command is used thusly:

Insert a blank CD, tell the finder to ignore the CD and continue.

type:
sudo ./cdrdao write -device IOCompactDiscServices blah.cue

If run as root cdrdao will use high priority threads to avoid underruns.
If you have a DVD burner you would use "IODVDServices" instead.
If your CD-R isn't known (like mine wasn't) you can select a specific driver.
For example this is in my .tcshrc file:

alias cue sudo /Users/anarkhos/cdr/cdrdao write --device IOCompactDiscServices --driver generic-mmc

thus to burn anything I just type "cue blah.cue"

Download it from here.