When deciding which plants to take inside with you for the cold months, keep in mind that pelargoniums will do fairly well, as dry air doesn't bother them much. Wax begonias also don't require a huge amount of light or humidity. But I've discovered a few more unusual types which will also produce during the winter.
I've had my double tropical hibiscus Kona for more years than I care to remember. It is three and a half feet tall at present, and about as wide, and would probably have grown bigger if I hadn't stopped repotting it. It will bloom off and on all winter in our big south-facing front window.
It does drop quite a few leaves after being brought indoors in the fall, as it adjusts to the lower light levels. So it looks a bit bare over the winter months, but that just makes it easier to see the flowers! I have a few other tropical hibiscus plants that will also throw out a bud once in a while, but none of them do so as often as Kona.
Justicia brandegeana variegata doesn't seem to bloom at all when it is outdoors. That's probably how this variegated shrimp plant contrives to flower for most of the winter under grow-lights, as it gets a lot of rest during its summer vacation! I suspect it may be one of those that requires shorter day-lengths to perform, since I keep the grow lights on only for twelve hours per day during winter.
My yellow allamanda will bloom both summer and winter. It doesn't generally have a huge amount of flowers all at once, but it almost always has some. I don't know for sure what type it is, as I purchased it marked-down at K-mart at the end of summer one year. And, by that time, its tag had long since disappeared! I did decide once that it might be nerifolia, but I can't recall how I came to that conclusion. If anybody recognizes it, please let me know.
Streptocarpus plants, like the one pictured in the thumbnail, are gesneriads, but don't look very similar to their African violet relatives. Though African as well, the streptocarpuses seem to prefer cooler temperatures than the violets do. So I keep them under the shop lights in the basement. As I have several, there is usually one or two of them in bloom from fall into winter, though they often get tired by spring. They are among my favorite plants, though I must admit that the tips of those long leaves are almost always yellowing.
The euphorbia plant was also missing a tag when I purchased it, but is probably one of the milii types. It was in constant bloom on a south-facing windowsill when it was young. But, like most of us, it slowed down as it grew older. So I cut it back drastically, and it does seem to have gone back to blooming now. Its shape isn't nearly as good as it once was, but you could probably say the same for us aging humanis mortales!
So those are some of my blooming-est plants. I'd welcome hearing which ones do well for you indoors too, so I can add to my list.
The only problem with such dependable types is that, what we see all the time, we tend to take for granted. I probably make more of a fuss over the temperamental varieties that may only flower once--or not at all--in their erratic lives. But it is old faithfuls like these that keep me going through the darkest days.