After Ryanair's mass cancellation of flights during the volcanic ash crisis in April and May (some of the time because of a genuine volcanic ash threat, other times for commercial reasons), many passengers tried to get compensation from Ryanair. Most failed.
But I've found that at least one passenger did get Ryanair to pay up. Not only that, but he got compensation for the flight he was forced to take with a rival airline.
According to the email I received:
I had a problem with Ryanair refusing to refund the cost of a replacement flight when my original flight was cancelled due to the volcanic ash cloud over Spain in May. I was unable to obtain a free replacement flight with Ryanair at the time because their website kept reporting an error, so ending up paying 550 Euro to book a new flight with them. They were refusing to pay for the cost of the replacement flight and would only refund the cost of the original flight (which was far cheaper at around 70 Euro).
Submitting a claim to the Irish small claims court was quick and easy, using the information on the ryanaircampaign.org as a guide. Ryanair agreed to refund the cost of the replacement flight and expenses resulting from the delay within 1 week of submitting a small claim application. It does work!!
Even if there is no Icelandic volcano threatening to ruin your vacation, Ryanair can often cost you more than you expect. Read about Ryanair Charges.
See also: Why Hate Ryanair?