It takes a while to covert.  After a year, we found ourselves becoming almost fully converted to the world's systems as opposed to the US systems.  35 degrees used to mean close freezing to me - now it means heat and sweat and stickiness.  Here are a few other:

We now know about how long a kilometer is.

Trash is rubbish.

When eating fast food, we leave the rubbish on the table instead of cleaning it up ourselves.

A can on Coke is 33 milliliters.

Dates are in this format  dd/mm/yyyy.

Dinner time is now closer to 9 pm.

You fill up a car in liters of gas.

When roads intersect they usually form a circle instead of a cross.

We line up on the right side of escalators if not moving ourselves

We can now provide exact change in Euros without staring at our palm for 10 seconds. Intersting side note: There is no 25 cent euro coin - only a 20.  We figure because the US quarter is based on the stardard system that has a base of 12 instead of the metric base of 10.  Royale wi' Cheese.

The education after high school is called university

The 24 hour clock (military time in the US) now works in our heads without calculation.

There are no restrooms of even bathrooms - only toilets and WC's.

When we pay for something, we expect to pay the price on the tag (without tax added at the end).

When calling, we automatically want to start with a "+".

 Of course, this means that we now have to de-convert.