Hostels.com engages in something very similar to DCC, except rather than switch to your card's currency, they switch arbitrarily to USD. (Which, for many people, will be the same thing. For many others, it will be even worse than DCC.)

Their main pages have a currency drop-down which allows you to choose many currencies. (However, they hide the fact that they only allow payment in three currencies.) So, you can look up a hostel to book in Australia, have it set to AUD and see this:

"12% Downpayment / Deposit: AU$53.28" next to the "Book now" button.

Clicking that button takes the user to the payment page, on which it is stated "12% Downpayment / Deposit: US$45.38"

This is, unsurprisingly (as hostels.com is run from Ireland, apparently a world leader in DCC), about 5% higher.