There are often a lot of water loving marginal pond plants in public greenhouses and conservatories. I know the one near my house has a lot of different kinds that you wouldn't be able to find in the wild, simply because it is too cold.
They have massive lily pads, at least three feet across, as well as lotus flowers and cattails (which are found in the wild around here, actually). They also have pitcher plants, which are my favorite.
They usually hang them from the ceiling but if you stand on tip toe you can see into the bottom of the plant where the fly is captured.
It's pretty interesting and a good place to hang out in cold weather.