FYI - The offers on the website have been updated since they were due to expire tomorrow. The new ones now expire in July '07. The good news is some of the deals are even better! The Tower of London offer has gone from "Buy one get one 1/2 off" to "Buy One Get One Free". That's at least an additional one rubber duckie in savings! ;)
If you are due for a visit soon (or even later) it is well worth a visit as there are opportunities for significant savings!