There are a couple of problems facing the world. Environmental issues, space crunch and rising costs for nearly everything are some of the most discussed topics. If you could create a solution for say, the high costs of housing in metropolises by designing a low cost and environmentally friendly solution, you could attract a lot of interest.

On the other hand, if you are more interested in the futuristic aspects of engineering, the fields to choose from are transportation, infrastructure, military and of course computing. A project based on any of these should succeed.

And if all fails, simply turn in a Dyson sphere model, saying you don't have the resources to make a real one, but are not opposed to helping build one. ;)