First, wow. :-)
I don't know of anyway of reading it on a Mac without a bit of trickery. If the information is absolutely critical, you could try running a copy of OpenStep in VirtualPC. That *should* allow you to read the floppy. Alternatively, call up Apple and ask if MacOS X server reads NeXT formatted floppies. If it does, find someone with a copy of MacOS X Server who'd be willing to pull the disk contents and email them to you. (1.4 MB. Oooh.)
Anyone else have an idea?