Java fern, java moss, ancharis, moss balls, small swords, bacopa, duck weed and I am seriously considering trying some frogbit.
I am going to go ahead and try it - the worst that can happen, I figure, is I will have to put the filters back on. :)
OOPS - forgot to add guppy grass as well.
I am ONLY trying this on some 5 & 10 gal. tanks with only one betta in each (no tank mates). I have a couple 3 gal. bowls with heat & small internal filters & those I will leave filtered even with the floating plants that are in there!