One of the best appetizer raves I ever got was from something very easy. Purchase thinly sliced salami from the deli. Roll pieces to resemble a cone shape. Place on cookie sheet seam side down and cover; refrigerate for about 1 hour. Soften cream cheese with a little lemon juice and dill. Put into a pastry bag and flute into the salami rolls. Refrigerate until needed. A little work up front but no effort that day at all.

Also, what about brocolli or spinach breads from a local bakery that you can slice and just warm up ahead of time.

By the way, check out the book 365 appetizer and hors d'ouevers and I'll bet you will get lots of ideas.