Living in the Eastern Cape in South Africa when I was expecting my children - I craved "strong" tasting food. Not much in that area to be found, it seemed, and at work there used to be hot mustard on the tables in the cafeteria. I got into the habit of putting it on just about everything. To this day I make my tuna salad sanwiches thusly: mustard on the bread/roll, lettuce, tomatoe (salted and peppered), occasionally I'll add a slice of strong cheddar to the sandwich. MMMMM. I met an Orthodox Jewish man from Israeal and we struck up an instant friendship when we noticed we liked our tuna sandwiches the same way.
Otherwise, we keep the same mustards as Ishbel mentioned. Can't live without the Coleman's - it goes into a lot of things. Sandyj