Brain teasers that only geniuses can solve
The true mark of a genius is not how well he or she performs on IQ tests or in school (which emphasizes memorization and robotic regurgitation of that info), but how adept that person is in conceiving outside-the-box solutions to novel challenges, such as these:
What can someone do while resting between exercise sets that will do considerably more than the exercise itself to help that person lose weight? I realize that burning fat while sitting or standing likely seems impossible for inside-the-box thinkers, but it is indeed possible. How?
How could welfare recipients receive more (even much more) than they now do while the welfare burden on taxpayers is significantly reduced? (answer)
How can racists quickly lose their racial animosity? (answer)
How could governments have roads plowed free?
How could governments have grass (in parks, along roads, etc.) mowed free?
How could snowmobile trails be kept perfectly smooth at all times without trail groomers? Background info for people who are not familiar with snowmobiling: For a variety of reasons, snowmobile trails are prone to quickly develop bumps that are often endless, forming a washboard surface that makes snowmobiling much less enjoyable. Snowmobile trail groomers—essentially road graders for snow—are periodically sent down trails to smooth them, but bumps often quickly form again. There aren't enough trail groomers, or operators, to keep all trails smooth at all times.
You want to extract as much caffeine (& other goodies) from your morning cup of tea. How can you do that without squeezing (or otherwise compressing) the bag, or using a centrifuge or anything else that imparts straight-line or curved acceleration or deceleration? You must use the same temperature and pressure, so you cannot use a vacuum to induce room-temperature boiling.
How can you legitimately make money by giving people things they want? How can your kids do the same thing?
How can an online service help you meet people in the offline real world even if they do not participate in online dating?
How can an online service enable you to contact people on paid dating sites without paying those sites?
Without using a robotic vacuum or maid, how could you keep your floor clean without manually vacuuming it or otherwise taking time to cleanse it?
How could we eliminate every cell phone company, and every cell phone tower, in the world while giving people MUCH better cell phone coverage at much lower cost?
How could you hang your house key outside, with a HOUSE KEY HERE sign pointing to it, so you never need to worry about locking yourself out of your home, without giving potential burglars an easy way to enter?