Not only does it smell great, clove oil can work wonders when working with an extensive palette and/or custom colors.
One of my favorite materials to use in the studio is clove oil. I don't use it that often these days, since I'm typically painting with a limited palette. However, when I am working with a large extensive palette (12 or more colors), or custom colors (greyscale, premixes, etc), clove oil is a great way of preserving these colors and extending the drying time by weeks.
Clove oil takes forever to dry. When you mix a few drops with your oil paint, you can extend the drying time of the paint to about a month. This is really useful if you want to set up a large palette of colors. I usually add about three-five drops to a silver-dollar size amount of paint.
Now, we don't want our paintings to take a month to dry... so that's where the Liquin comes in (or any other alkyd-based medium). By mixing a little Liquin with your colors as you paint, your painting will dry in just a day or two, but your palette will never dry!
Another idea is to use an alkyd white paint instead of a medium. Since white paint will work its way into your entire painting, you won't need to worry about an alkyd medium. Just put clove oil into all your colors, and squeeze out only the amount of alkyd white paint that you'll need for the day.