It depends, you can use single quotes like: 
my $recipient = 'some.g.guy@bigcorporation.com';

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or double quotes with a backslash before the @ character so it will not be interpolated: 
my $recipient = "some.g.guy\@bigcorporation.com";

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In reply to Re: Strings with @ by Marcello
in thread Strings with @ by Anonymous Monk

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