Ignoring the draught cask ales that would be near impossible to find beyond these shores, I would recommend the following bottled beers.
From the British Isles:
Marble Lagonda IPA
Downton Chimera IPA
Thornbridge Jaipur IPA
Guinness Foreign Extra Stout
Hop Back Entire Stout
Youngs Special London Ale
Wye Valley Butty Bach
From Europe:
John Martin Pale Ale
Duvel
Timmermans Gueze
Jever Pils
Lowenbrau Oktoberfest
From the US:
Harpoon IPA
Goose Island IPA
Brooklyn East India Pale Ale
Brooklyn Black Chocolate Stout
From the Antipodes:
Little Creatures Pale Ale
From the British Isles:
Marble Lagonda IPA
Downton Chimera IPA
Thornbridge Jaipur IPA
Guinness Foreign Extra Stout
Hop Back Entire Stout
Youngs Special London Ale
Wye Valley Butty Bach
From Europe:
John Martin Pale Ale
Duvel
Timmermans Gueze
Jever Pils
Lowenbrau Oktoberfest
From the US:
Harpoon IPA
Goose Island IPA
Brooklyn East India Pale Ale
Brooklyn Black Chocolate Stout
From the Antipodes:
Little Creatures Pale Ale