Well, the ones I know are:
Clove:
- Gongora clavidora (I smelled a hybrid of this plant, and the scent was strong enough to fill the immediate area)
- Huntleya wallisii (this one's a tough one to grow, though, and the fragrance is a bit closer to that of star anise).
- Huntleya meleagris
- Rhynchostylis gigantea (it's actually a combination of clove and citrus, kinda like orange tea).
Cinnamon:
- Lycaste aromatica
Citrus:
- Vanda denisoniana (these smell exactly like orange blossoms)
- Aerides species (odorata and lawrenceae, I believe)
- Sedirea japonica
Can't think of more right now, but I'll post again if I think about them. You gotta also keep in mind that fragrance varies from clone to clone; while one plant of a certain species/hybrid may be richly fragrant, another one may not.