It could feature a rapidly departing Carlos Tevez, his Louis Vuitton suitcase stuffed with cash and his City shirt tossed into the nearest bin.
The suggested slogan: "Welcome to Reality."
It would be a fitting riposte to City's infamous "Welcome to Manchester" billboard, which celebrated Tevez's shock transfer from United in 2009, taunting the bigger club for its supposed lack of true Mancunian credentials. (Old Trafford lies just outside the city boundary, and many of its faithful come from considerably farther away.)
Because, while City fans are entitled to be angry at Tevez's alleged refusal to take to the field at Bayern Munich on Tuesday, they have no right to be surprised.
Tevez showed no concern for the feelings of United fans when he defected to City, blaming Sir Alex's poor management. Back then, his turncoat nature brought great joy to the blue half of Manchester.
Did they really believe he would treat them any differently when it was time to hop back on the gravy train? Did they think they had won his heart with their self-deprecating humour, crazy goal celebrations and yarns about Mike Summerbee? Perhaps they hoped he would be overwhelmed by the purity of their Mancunian genes.
Well, he was not.
It seems he became so keen to leave Manchester that he could not wait for City to find a full-price buyer, as they had tried to do in the summer.
Instead he waited for the club's greatest European night in a generation to stage a fire sale, with the damaged stock being himself. With Fifa financial fair play regulations around the corner, City cannot simply absorb a £40m (Dh229.3m) loss and let him rot in the reserves until his contract runs out, nor even accept the amusing offer of a loan deal from the Irish minnows Limervady Rovers.
They must now sell him, in January, for whatever they can get.
Glasgow Celtic fans feel similarly betrayed by an unknown local player in whom the club invested. Islam Feruz, a 16 year old billed as "the Scottish Wayne Rooney", was lured to Chelsea on a pre-contract deal despite Celtic reportedly saving his family from deportation to their native Somalia, and moving them from a Glasgow housing estate into a more leafy area of the city.
We might feel more sympathy for them as they achieved great things with local players in 1967.
Their investment in him was shrewd and profit-driven, but nurturing a talented boy seems far less hubristic than snaffling a rival club's marquee player for fun.
True, Feruz was not obliged to swear allegiance to Celtic for life - he has every right to play the market, just as many lower-league Scottish players snaffled by Celtic did. But Celtic fans have more right to vent their fury at his betrayal than City fans do over Tevez. They can at least claim to be surprised by it.
Graeme Souness described Tevez as one rotten apple. Frankly, I have a nasty feeling the whole tree is sick but, for the sake of our own sanity, we must continue to consider our heroes without prejudice: ethical until proven mercenary.
As an Englishman, I should be delighted at the controversial bagpipe ban at the Rugby World Cup in New Zealand.
Scotland’s psychological loss is surely England’s gain as the auld enemies clash in Auckland on Saturday.
So I should be congratulating the New Zealand authorities for their steadfast enforcement of the blanket “no musical instruments” rule, which extended to one fan’s pipes being impounded by police last week.
I should be expressing righteous indignation on behalf of fans, officials and players who do not wish to endure the noise described by Alfred Hitchcock as like “an indignant, asthmatic pig”.
However, on this issue I will back the bagpipes.
Firstly, bagpipes are more than a musical instrument. Their haunting sound is deeply woven into Scottish identity, and should be treated with the same reverence the Kiwis demand for that aggressive morris dance they like to do before kick off.
Secondly, an attack on Scotland is an attack on all emotionally repressed northern hemisphere countries who rely on certain stimuli to get them revved up.
(Yes, that means us English.) Thirdly, the Scots are famous for their rebelliousness and inventiveness. When the English banned them from training their young men in warrior skills, they invented Highland sports.
Ban the pipes and they will simply improvise another stirring instrument using non-vetoed items.
Imagine Mel Gibson bellowing: “You can take our pipes, but you’ll never take our comb and paper!”
Finally, and most crucially, I am backing the bagpipers because it makes me look like a fair and noble Englishman (which the Scots hate), safe in the knowledge that they could not win today even if the entire Royal Scots Dragoons’ pipe section stood beneath the posts playing the score from Braveheart.