Feliway

[niemand88f]

I only notice the smell when I'm actually holding the plug, not at other times. You could try using the spray instead, since that doesn't spread as well through the air you might notice it less- although that means it might not work as well for your cats too.

[dottyblue]

I also only notice the smell when I am holding the dispenser. Strange.

Have you tried the calming collars? They release the same pheromones as the Feliway, but it's always with your cat. This has worked well for my guy.
www.amazon.com/GOODbehavior-Pheromone-Calming-Collar-Cat/dp/B0026JAKWG/ref=sr_1_1?s=pet-supplies&ie=UTF8&qid=1345135080&sr=1-1&keywords=calming+collar+for+cats

[kellbell191]

I also don't notice the smell. But man do I love that stuff. Night and day with my monsters.

[Ramz-ee]

I don't notice the smell and I'm super sensitive to smells. However I do notice the spray on the walls above the plug-in. It wipes away, but it's kind of annoying if it's in a high traffic area.

[polarbearfans]

I have never noticed a smell.