Replying to Please help me come up with an idea for class

I have a class in entrepreneurship and we have to come up with an idea to work on over the course of the semester. So basically i'm having a lot of trouble figuring out what to do, at first i was looking at the feasibility of an indoor ice climbing wall (and yes they do really exist - outside of the US) but that was too expensive and just not a good idea.

I'm wondering if you guys have had a similar class or any ideas or some experience where you have seen something that requires a need that isn't filled yet. it could be a service, or some new product. i just need something to work on and its not for real but just for the sake of doing this hypothetical project on.

so please please please if anybody has suggestions of anything i would be super appreciative if you guys could help me or brainstorm with me.....thanks!