Any particular reason for asking?
I have 3, a geranium that an old neighbour gave me, a bombproof Christmas cactus that flowers at random intervals and a money plant that was an unwanted gift.
Once upon a time I had a couple of streptocarpus from my mum's collection but I can't remember what happened to them.
I could probably fit a few more on the living room window but I don't seem to have the same love for houseplants as those outdoors, probably because they're not covered in pollinators.