Yup, there are smaller ones, as mentioned..
Remember that there is a HUGE personality difference between boas and balls.. Which is why most keepers usually focus on one or the other..
I have mostly bps.. but i do have a few BCI .. They are great, but are SOOooo curious.. my husband is NOT a fan of the boas.. They make him nervous, because whenever you walk into the room, they sit up and look at you.. lol