Durex in Mexico is the brand name for sellotape....
the first time i heard this it was one of those frosty old matron types in the post office
'Here borrow my roll of durex'
i fell about laughing

And don't forget a rubber in the UK is an eraser but not in the US
When i started teaching in Mexico at a University my male students thought I was a bit 'full on' when I asked them if they had brought pencils, notebooks and rubbers to class.

And every so often when i couldnt find my board eraser i would say... any one seen my big rubber?

it was a jesuit university too... so it was all a taboo subject