The Zenith Minisport used 2" floppies (the same
media used on the
Canon Xapshot camera (and some others).
As has been mentioned, there are also 2.8" and 3.25" inch floppies.
There's also a 12" floppy, but it doesn't hold much:
:-p
The largest floppy (flexible magnetic disk) I ever saw was at least 14 inch.
This was at IBM in 1985 or '86, although I'm pretty certain it wasn't an
IBM product. We used it for some sort of audio or speech synthesis
system. The drive was a separate box about the size of a PC system
unit, and the disk occupied almost the entire footprint. Notable
features were the envelope - thin white card - and the window therein
for the head, which ran from near the centre to near a corner of the
envelope. (I only ever saw the one disk.)
Philip.