Ok, I have a project for you technical folks. It won't get you the glory of developing the perfect hydrogen fuel cell or the newest wind turbine. But it might have a bigger impact than either. And it will make you rich. So I need someone out there to develop, perfect and patent the reusable condom.
This is not a joke. The condom is the most commonly used form of birth control in the world, especially during sexual activities that pose a high risk of pregnancy or disease transmission. The people who are most likely to use them are more likely to be poor than those using other forms of birth control. They are more likely to be in temporary or at least unmarried relationships, so that the pregnancies that result are more likely to lead to single parenthood for women. They are cheap by industrial standards, but expensive by the standards of most of the developing world. And because they are single use, and most human beings have sex fairly often, keeping yourself in condoms can be pricey. Lack of a condom, or lack of funds for condoms, is a classic reason for accidental pregnancy or disease transmission.
So what if everyone had their own? What if condoms could be reused hundreds of times, like diaphragms, or menstrual cups? What if you could wash it was soap and water, squeeze out a drop from a little tube of spermicidal lubricant, and have sex without worrying about breaking the condom budget. What if everyone in Africa could afford condoms, because they only had to buy 1 per year? How many unwanted pregnancies would be prevented?
It has got to be possible - both the menstrual cup and the diaphragm already exist, although both are made of materials thicker than most people would want in a condom. But there are very fine, very strong materials out there that would also be impermeable to disease organisms.
Regardless of your take on the population issue, I think we all can agree that the world is a happier place when people who don't want to have children don't get pregnant. So c'mon, engineers - save the world, change a condom!