[dba-Tech] Jet clone?

Back in the days of DOS, there was an incredible utility called Jet. It was
in essence a very smart equivalent to xcopy, but infinitely smarter. For
example, you could:
Copy source dir to target dir, specifying only replace existing files;
Copy source dir to target dir, leaving files with same datetime alone and
copying only the successors;
Copy source dir to target dir, making any subdirs required, while leaving
alone any files of the same datetime;
Copy all the files from source dir to target dir that do not already exist
in target dir;
Copy all the files created today from source dir (c:\" to target dir;
Copy only the files that exist on the target that exist also on the source,
and copy only those files that are newer, recursing through the dirs.
You could pass all the args you need on the command line or write a batch
file and pass them from there.
Best of all, it did something like xcopy but IMO smarter: it read the file
sizes and used available memory to grab as much as it could, then did one
write (to perhaps several filenames), dumping all the ram-contents in one
single write, then reading more if necessary until it was done. 
In the DOS world, it was insanely quicker than xcopy.
And so on...
This utility, as I recall, shipped with a RAM board that I bought, that
contained 8MB of RAM and let me use it all as EMS RAM. It was the most
incredible file-copy utility I ever used. Sadly, it was DOS-based. I wish
there were a utility like this that works in the WinWorld, but I have not
yet found it. 
Given the era of this program, several enhancements would be required to
deal with contemporary systems:
Recognize CDs and DVDs;
Recognize long file names;

Does anyone know of anything similar? It couldn't be written in Access and
perhaps not even in C++ to deliver the performance that Jet delivered. I
think this requires assembly language. Perhaps not.