Aside from Caponata, Salmon and Tuna that are already mentioned, capers are great with roasted bell peppers... very nice antipasto, also great for bruschetta...
Bake the whole peppers in the oven at 180°C/350°F for about 40minutes, turning them over once in the middle. Let them cool a little, when they are safe to touch but still very warm, peel off the outer skin, remove the seedy centre, then tear them into strips, dress them with caper and pine nuts. Drizzle some good evoo over, serve them chilled or at room temperature.
* We use salted capers, and rinse them well before adding them to our food, they are still salty enough after rinsing, without rinsing, way too salty!!
* for roasted peppers, you can roast some garlic cloves together, then mash it and mix with bell pepper and other things... additional flavour!