When I book FR, it's always on a "throw away" basis, that is, I know that if I can't make the trip, I will just throw the tickets (electronic as they may be) away. They're so cheap that this is what they expect you to do (and there's no alternative anyway).

In February I had FR tickets for DUB-MAN-DUB which I couldn't use, so I just let them go without any quibble. After all, the total cost was less than GBP 30.

I had to change my arrangements slightly so I booked EI DUB-MAN, LS BLK-ALC and EI ALC-DUB. Much nicer airlines anyway.

Ryanair is really the pits (basically a mobile gambling hall), but is cheap as.