I would echo the above with Nelly Isler, onc. Twinkle and Onc. Sweet Heavenly. I also like the fragrance of my BLC (Mello Vista x Goldenzelle) x George King 'Southern Cross'...it reminds me of lily-of-the-valley.
As most of the orchids in my collection are chosen for their fragrance, this was rather a difficult decision but I think I must go with the Cattleya aclandiae and Phal bellina, at least for now. They might not be my favorite fragrant orchids but I like their fragrance the best.
The one that should smell terrible is my little Den. cucumerianum but I have not had it bloom yet so I cannot really say.
Some of my favs are Onc. Sharry Baby, Onc. sotoanum, C. Waianae Leopard and there are many more Catts that smell lovely.
None of mine smell too terrible, but I guess C. percivaliana fits that category in my collection. I don't like some that have too harsh of a lemony or soap smell either.
Aside from the normal good ones (Brassavola nodosa being at the very top), I'd have to say that I LOVE the smell of Fdk. After Dark. It's sort of a combination of menthol and pine, which sounds weird (and it is), but I find it very enjoyable, esp. at this time of year.
I have Bc. Little Mermaid and it smells nice, but the fragrance was very light this year.
Bulbo medusae has a sweet, earthy fragrance I love.
Oncidium Sharry Baby - sweet yummy fragrance.
Oncidium maculatum - smells like a mix of pineapple and banana.
Brassia New Start - Omg such a deep, sexy fragrance of vanilla incense.
Oncidium Speckled Spire - Very sweet like cotton candy.
Maxillariella tenuifolia - coconut!