Traffic. It's been plaguing our cities for years and isn't showing any signs of going away.
Auckland's got the City Rail Link and Harbour Bridge SkyPath to look forward to, but
China's "straddling bus", which would drive over the top of traffic, carry 1200 people and have ramps you can slide down to disembark is one example of creative thinking. The first prototype of this monster rolled out this week.
Then there's the urban gondola, which zips people through the skies from the CBD to the suburbs in countries like Turkey, Colombia and Spain.
Belgium has found that getting people on motorbikes is the fastest and even safest way to be on the road. If just 10 percent of drivers switched to motorcycles, it would decrease travel times for the remaining car drivers by eight minutes.
There have also been some creative suggestions for solving London's gridlock. One designer has suggested cycle lanes in abandoned tunnels beneath London's streets.
Then there's the idea of transforming Regent's Canal into a swimmable route - apparently separated from the passing boats, rats and floating rubbish.
Elon Musk's Hyperloop, which is less than two years away from testing, will shoot you through a tube to your destination. It's promising to take you 480 kilometres in half an hour.
These ideas might seem pretty far-fetched, but perhaps they're what's needed to put the brake on our rush-hour blues.