Maid of Orleans Jasmine blooms year round..Flower scent remind me of citrus blooms.
www.accentsforhomeandgarden.com sells Maids..they were 4.99, but don't know if prices increased. Plants are nice-sized, healthy and beautiful. I bought two, potted together, which made a compact plant..
Another is Murraya..Oh flowers smell heavenly.
If you have a lot of sun, citrus (especially Meyer's and Calamondin) bloom year round. Toni

Look thru the logees site. (www.logees.com) My Belle of India jasmine is an everbloomer, as well as the Four season gardenia.

Toni and ctreynard named the ones that came to my mind first, but also aglaia odorata, rondeletia splendens and hoyas lacunosa and obscura (and a few other hoyas that aren't as good smelling or powerful). My passiflora 'Ruby Glow' blooms nicely all fall and winter. A few begonias, but the 'Tea Rose' one I had didn't do much for me (though I hear there's better). Oh, and some cyclamens. Also cestrum nocturnum, but mine hates being indoors. Tea olive, but I killed my potted one. I'm sure the orchid people will have some for you....

Good ideas. Will check into these.