What benefits have people from other countries brought to London?

Many millions (if you're Chelsea FC)
Gypsy jazz
Working-class apathy
Tyskie, Lech and Zywiec
Cheap labour (hired from outside Wickes)
Beigels 24 hours a day
Less stiff upper lip
Antipodean slang: bogan, drongo, maaaate
Huge sunglasses in nightclubs (courtesy the Italians)
The world on your doorstep