Cars with switchable dip, either from the cabin for by simple switches on the backs of the headlights:-

Audi TT Mk I,

BMW E46 3-Series

BMW E39 5-Series

BMW E92 3-Series coupes

BMW 6-Series ('Tourist lever')

BMW 7 Series E65/E66 (2002 - 2009)

Ford Focus II (with adaptive lighting)

Ford Mondeo with bi-Xenon headlights

Ford Cougar

Honda Accord with Xenons have flat dip headlights so no need to switch.

Jaguar X-Type has switch to prevent dazzle when driving on right

Jaguar S-Type has switch to prevent dazzle when driving on right

Jaguar XF has switchable dip

Land Rover Discovery 4 HSE Xenons (but involves removing the grille first)

Lexus IS220d and IS250

Most Mercedes can be switched to dip down rather than to the left.

Mercedes CL: Command system automatically switches from LH dip to RH dip in Europe

Renault 4GTL with 1100 cc engine and built around 1980 

Renault 6TL (1970s model)

SAAB 9-3 Sports Wagon (lights dip down, not to the side)

Skoda Roomster

Skoda Octavia vRS with optional Xenon lights allows the beam to be put into 'Travel Mode' via the Maxidot computer. The lights remain in this mode until you switch them back. You are reminded that they are in Travel Mode every time you turn the car on. This doesn't switch the beam but simply flattens the kick-up on the left side.

Skoda Superb Mk 1 (has levers, but fiddly to get at)

Skoda Superb II Elegance (electrically)

Vauxhall Calibra

Vauxhall Zafira B with Bi-Xenon adaptive headlights have a switch within the cab.

Vauxhall Vectra 2002 - 2005 

Vauxhall Signum 2002 - 2005

Vauxhall Insignia with halogen headlights 

Vauxhall Omega CDX

VW Passat from 2001 - 2005

Volvo XC60

Volvo XC70

Volvo XC90 with 'Active Bending Xenon' headlights (Unfortunately these require the driver to go through 10 steps to switch from left dip to right dip, but revert to left dip whenever the engine is switched off. By September 2010 Volvo had no fix for this.)

Volvo XC90 with Directional bi-Xenon headlights