Pineberries are a strawberry derivative that taste like pineapple.
This unique fruit was bred from a wild strain of strawberry in South America that faced extinction until 2003 when a group of Dutch farmers saved it. Its genetic makeup is said to be identical to that of a strawberry, however it is a white berry with red seeds.
Because they are a brand new variety of fruit (they were just released earlier this spring), they are still very rare, but are currently being sold in the United Kingdom and Belize. (1)