Adult (16+) $28
Child (4-15) $16
Family (2 adults + 2 children) $85
20% off. If you are really desperate to be a trendsetter, firstie etc. then 20% is better than 0%. You also need to print the tickets, so that usually means skipping the queue for paying in person.
Madame Tussauds is famous for real-life wax figures of popular celebrities. "Brad Pitt, Kylie Minogue, Lady Gaga, President Barack Obama and the Queen" are some of the figures (quoted by travelzoo).
Travelzoo link: http://www.travelzoo.com/au/holidays/-28-Opening-Special-Mad…
It notes that there are a limited number of tickets, but that could be a ploy to make you buy them.
$28 seems excessive for a wax museum…