www.skyscanner.com - flight search engine
www.expedia.com - another useful flight search engine
www.drungli.com - adventure generator - the site looks for any cheap flights, no matter where
www.kayak.com - another good flight search engine
www.kayak.com/explore - see where you can go and for how much
www.flightright.co.uk - compensation for flight delays and cancellations
www.sleepinginairports.net - a guide to how to sleep in airports