I suddenly have an interest in this, since I'll be travelling quite a bit (Amsterdam-Vienna). Do you have any hints? I've had trouble finding anything that actu

I suddenly have an interest in this, since I'll be travelling quite a bit (Amsterdam-Vienna). Do you have any hints? I've had trouble finding anything that actually saves money. To add at least a little value: matrix.itasoftware.com has found trips (e.g. Amsterdam-Tallinn) for me that the local (Dutch) travel sites didn't. I was pleasantly surprised by this.