Expedia fares can be SHARPLY cheaper if you book hotel accommodation as well, since this lets them access the 'travel agents only' discounted fare classes.

The genius of Expedia is that you only need to book 1 nights accommodation, even if you are away for 2 weeks. This makes it far easier to make savings. (Obviously you don't use the 1-star hotel you book!)

The downside is that you can only book economy. However, in the UK you can book J or F via lastminute.com - although the downside with them is that you DO need to book the hotel for every night of your stay.

I booked Swiss flight to Zurich for Easter and we saved £40 each this way. I may not get any miles but its only a Y flight anyway so I'm certainly not missing £40-worth.