x86/DOS system backup via rs232?

[Jules Richardson]

As per subject line, does anyone know of any util that will back up an x86 
PC running some variant of DOS (MS, Compaq etc.) via rs232 to a remote 
system? (Linux preferable on the remote, but other options exist)

I'm not finding anything via Google, but it seems like the sort of thing 
that some of the folks here may have done for their systems in the past.

I'm thinking something that will do a sector-by-sector transfer from a 
given partition (maybe only in-use sectors, implying some minor 
intelligence on the remote end to covert into a raw image, but "send 
everything" mentality is better than nothing) - extra points for retrying 
bad sectors.

cheers

Jules