4th split allows you to split large files into blocks small enough to fit on floppies. You can make the blocks dos-compatible (so you can unite them with old zip utitlities), standard (you will need to include a tiny unpacker) or self-uniting. You can change the size of blocks for any kind of floppy, even the ancient single-sided ones. One file can be split into no more than 1000 blocks, but that's more than enough.
The interface is intuitive with two explorer windows, one for the source file and the other for the blocks. 4th split also includes a nice Favourites feature that allows you to jump to your most frequently used folders. There is good help system as well. The program does its work brilliantly, it's tiny and free. Best file-splitting tool of all!