MISC. SPICES
Although spices are used spiratically at best in modern brewing, there was a day when they were popular. These were the days preceding introduction of the hop, when the role of microbiology was not understood. Off-flavors were more common than in today's controlled brewing environment. It has been suggested that this was the reason for using spices, as they could hide significant imperfections. Perhaps modern the use of spices is a hold over from those times.
They may be added at the end of the boil but seldom during, or in the secondary fermentation. Keep in mind their influence will deminish in time.
Ginger:
My only experience with this spice was in a stout. I added a sliver of fresh ginger into every bottle a week after bottling (I was young!). The beer was not contaminated, had an verwhelming ginger flavor and gushed soft foam upon opening.
Cumin:
Unusual (duh!). Try some Wit Amber if you're curious.
Paradise/Cardamom Seeds:
An old, exotic spice said to have been grown in the hanging gardens of Babylon. One of the worlds most expensive spices, it is aromatic (used in some perfumes) and a reputed aphrodisiac.
Nutmeg:
I put this in my Holiday Barley Wine. I prefer it in nut form, broken into large pieces with a hammer. 1 nut per gallon in this heavy beer (OG:.122, TG:.040) is plenty.
Sweet Gale Seeds:
Noted in Radiate's book on Belgian Ale. Has a bitter, aromatic leaf. I put some in boiling water to check out its aroma. It was a dead ringer for fennel sausage.