When there is no capital to start one of the smartest things to do is to start a business based only on ideas. You should not be looking at starting something that requires too much inventory and logistics. Make a list of what you know how to do. what you know might be novel and new to others. look for idea base, virtual businesses to start. they can include;
1) marketing consuting
2) Event planning etc.

If you think hard enough you are sure to come up with something