If you are flying from Paris to Madrid or vice versa book with Vueling (vueling.com) Make sure you sign up for there promotions by giving your e-mail. About every 6 weeks they have flights for 10 euros + taxes which makes a one way trip from Paris to Madrid for between 30 - 40 euros taxes included. I fly with them all the time. Last week did Paris - valencia. Valencia - Seville. Malaga - Barcelona and Barcelona - Paris. the price for two tickets 210 eruos taxes included for 2 people. Serious company with new airbus A320's and we haven't crashed yet.