It's tricky, because plants that are supposed to be non-toxic are usually talking about cats and dogs and children, and not necessarily about rabbits. And even if a plant was non-toxic, it might still upset their guts because tropical and desert plants that do well in our homes are not exactly something that's natural for our bunnies to eat...
What I do is mostly focus on just keeping the plants out of reach and make sure they can't drop leaves on the floor that could be eaten. For example,
snake plants are toxic, but they have no leaves to lose, so as long as they're on my window sill where Casper and Sophie can't get to they're not a danger (they're really easy plants to take care of, by the way, but not everyone finds them very pretty!). Desert cacti and some jungle cacti don't drop leaves, either, and are also easy to take care of. So, that's your typical cacti and ones like the
fishbone cactus. Small succulents like
Echeverias and
Haworthias won't drop leaves on the floor, either, and are easy to take care of, too.
I know succulents aren't everyone's thing, though. I haven't had my
pancake plant drop leaves, either, and that is also an easy plant to look after, and the
spider plants that nap91 mentioned are good and easy, too.
All the plants I've mentioned except for the snake plants are safe for pets if I did my research correctly, but, again, I can't say for sure if that means they're safe for rabbits, too...
