For once, good on Ryanair.
There are far too many unfairly disriminating taxes on aviation that only serve to (perversely) increase emissions. This may be due to tankering fuel from regions of lower fuel price (in the case of a fuel tax) increasing total fuel burn, or simply people being priced onto more polluting methods of transport such as cars or trains; (Yes trains - Think of the level of noise of a train times the number of people exposed to this noise at close quarters).