Kerryn, do you have an icecream maker? I have one, and often make icecream with just sugar, milk, cream and some kind of flavouring. You could follow the recipe to the point where the eggs are added, and instead of adding the eggs and cooking the custard, just chill the mixture and then churn it in the icecream machine. It won't be as rich an icecream, but it should still be delicious.