if they are sat in the middle lane with no other traffic you need to loop them
drive up in the inside lane. change to outside lane. overtake. pull into inside lane. allow them to over take. repeat until they get the message.
( Vipros. clever got me this far, then tricky got me in, Fri 16 Oct 2009, 16:29, 4 replies)

i prefer undertaking
while shaking my head like a smug irritating bastard. but that's because i'm a smug irritating bastard.
(Alphabet Soap boshboshboshbosh, Fri 16 Oct 2009, 16:40, closed)

I do that too
I think my record is seven times.
(Vice Admiral Sir Charles Cockbrush KCB MBE DSO, who is finding it increasingly difficult to log into b3ta.com wants to duck your aunt and kick your puppy, Fri 16 Oct 2009, 16:50, closed)

Even better,
I get in the middle lane in front of them, slow down very gently, and just as they pull out into the outside lane to overtake you, pull into the inside lane leaving them stranded in the outside lane and speed up. For some reason this upsets them even more!
( Blind Meach Cautiously optimistic, Fri 16 Oct 2009, 17:24, closed)

Get in front of them and slow down

( idonthaveafunnynickname Drink-Aware? Sure. I'm aware I want another drink., Sat 17 Oct 2009, 1:49, closed)