My brother has a venus fly trap, and while it isn't getting the little fruit flies, it does really help with the big fly population, there was three buzzing around the last week and I haven't seen them yesterday or today, and the venus flytrap has to bulging traps closed, so they do work, you just have to make sure there isn't something else the flys are more attracted to, like the garbage or compost.
I looked last night and there wasn't one fruit fly around the basket, I hadn't done anything yet! I asked my brother and he said he threw away a banana.