I'm going to have to put in a Rusty Nail.
60% Scotch (nothing too strong), 40% drambuie, and Ice. This is one of the most divine drinks I've ever had.
Another one: Drambuie and Soda. Pretty simple, but you use two lime wedges, one to squeeze and drop in, the other to garnish. This one can be mixed very strong without you knowing it.
I accidentally mixed one up the other day that had about 4-5 shots of Dram in it, and I didn't notice until 20 minutes later.