On second thought, it might not be that odd. Most of us remember cinnamon sugar on French toast from our childhoods (or perhaps even more recently). Now it is time to expand on cinnamon sugar and start experimenting.
One old standby is vanilla sugar, which, like all infused sugars, is made easily enough. When you have used the vanilla bean pods in something like ice cream, take the pods and instead of throwing them away, submerge them in some sugar and place in an airtight container. Leave for a few months, and when you open the jar, you will have gorgeous, vanilla-scented sugar.
Victorian cooks were especially fond of lavender sugar, as well, and used it in almost everything. I have recipes for cakes, cookies, pies, ice creams, and more that use lavender sugar, and it's delicious in tea, too!
If this seems odd to you, remember that herbal tea? Did you put sugar in it? Ah, now this doesn't seem quite so eccentric, right? In any case, to make herb sugars of any variety, it works the same way. Spices should be finely ground to mix with the sugar. Herbs should be fresh. Simply submerge the fresh herbs completely in the sugar, and wait a few months, shaking the sugar each week or so. Sift or pick through the sugar with tweezers to get the pieces of herbs out, and you will have exquisitely perfumed sugar to use in baking, in tea, or anywhere you want to have a spicy or herbal sweet taste.
Looking through baking recipes, especially from earlier ages, is a great way to get a sense of how to use herbal sugars, but even if you never use them for anything but to sweeten your tea, you will have made your life that much more exciting. And as a last resort, infused sugars make wonderful and thoughtful presents!