This is a titty fruit. Please don't eat (or suckle) it

Also known as the nipple fruit or its Latin name, Solanum mammosum, the titty fruit is related to the potato and the tomato. Even though it looks delicious, please don't put it in your mouth, as it is poisonous unless prepared properly. However, its usefulness extends beyond its delightful name and appearance. From Wikipedia:

The juice of the fruit can be used as a detergent in place of a washing powder, making it similar to the soap nut. The Kofan People of Colombia and Ecuador use the plant as an insect repellent, primarily against cockroaches. The fruit works as a repellent because of the toxicity of steroidal glycoalkaloid.

Although the fruit is poisonous, it can be cooked and eaten like a vegetable when it is unripe.[citation needed] It provides a good source of calcium, phosphorus, iron and vitamin B.[4]One way that the fruit can be prepared is boiling the whole fruit and drinking the juices once boiled. In the Philippines, not only is the fruit eaten, but the leaves are also prepared as a tea considered to be anodyne, a mild narcotic.

[via Kuriositas]