One of the secrets of budget travel is to go through cheap airline hub airports. This is airports that are well connected with a lot of low budget airlines and destinations. From these airports you can expect to find cheap flights to 10+ destinations in other countries for under 100 euro one way. In some cases you need to be very dynamical with the date of travel, while some airlines have daily flights for about the same price.

Example of airline hubs are:

Brussels
Albania, Algeria, Bulgaria, Croatia, Cyprus, Denmark, Estonia, Egypt, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Kosovo, Latvia, Lithuania, Macedonia, Morocco, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Spain, Sweden, Switzerland, Tunisia, Turkey, UK

Dubai
Bahrain, Egypt, Ethiopia, Georgia, India, Jordan, Kuwait, Lebanon, Nepal, Oman, Pakistan, Qatar, Saudi Arabia, Sri Lanka, Sudan, Syria

Frankfurt
Austria, Bulgaria, Croatia, Cyprus, Denmark, Egypt, Finland, France, Germany, Greece,  Hungary, Ireland, Italy, Latvia, Lithuania, Morocco, Poland, Portugal, Spain, Morocco, Norway, Portugal, Spain, Sweden, Turkey, UK

Milan
Albania, Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Kosovo, Latvia, Lithuania, Malta, Moldova, Morocco, Netherlands, Norway, Poland, Portugal, Romania, Russia, Serbia, Slovakia, Spain, Sweden, Turkey, UK

(Flight destinations above can be found cheaper then 100 euro)

Within a week I have a flight out of Egypt to Brussels. From there I have no fixed plan, but will report  as soon as I know more.