I think London is the worst... You can easily have $150 - $200 in taxes.
Yup. Saw this "great" British Airways fare to LHR, and then priced it INCLUDING taxes, and found it to be about $300 more than an American Airlines fare to FRA through ORD, or a LH fare to FRA via PDX, or a NWA fare to AMS (direct) or FRA (through DTW).
Now, granted, BA has great service and it was the direct SEA-LHR flight, but still...