Ice cream:

2 cans (20 oz. each) crushed pineapple
2 Tbsp. lemon juice
2 Tbsp lime juice
1/3 cup sugar
1-1/2 cups whipping cream, whipped. {Here is a tutorial on how to whip whipping cream, just in case you've never done it before.}
Juice:
Pineapple juice {As much or little as you want}
Sugar, to taste