At the end of the 1991-92 season the two clubs came together and, backed by local businessman Max Griggs, Rushden & Diamonds made their debut at the start of the 1992-93 season.
Whether the proposed merger of Wimbledon and QPR goes through or not, the 'm' word will continue to be bandied around in sporting circles whenever a club faces a financial crisis.
Some unions have ended in dismal failure.
But while Dons and Rangers fans will be spending Thursday in a state of shock, depression and foaming-at-the-mouth outrage, they should remember that the last 10 years have seen a few very successful new unions.
Rushden Town or Irthlingborough Diamonds were, individually, unlikely to find themselves in the Nationwide League, but today they stand stronger and on the brink of that very achievement.
At the end of the 1991-92 season the two clubs came together and, backed by local businessman Max Griggs, Rushden & Diamonds made their debut at the start of the 1992-93 season.
Their first game, against Bilston Town in the Southern League Midland Division, was watched by just 315 fans, but the club did well, finishing second in its debut season.
A new stand for the following season brought more fans and success as the club was promoted from the Midland Division.
They went up to the Conference in 1997 on the back of Griggs' Dr Martens footwear business fortune and, after a couple of near-misses, should be up in the big-ish time of the Third Division by August 2001.
Months of protest
Similarly, Inverness Caledonian and Inverness Thistle could only dream of taking on the big boys of Scottish football and coming out on top.
The two Highland League sides merged at the start of the '90s, with the town's third football team Clachnacuddin pulling out after initial talks.
Thistle's then-chairman, John McDonald, faced months of protest from fans of both clubs, including a mass moonie from 60 furious supporters.
Luckily, he closed his eyes, gritted his teeth and got on with things.
By 2000 Caledonian Thistle were up to the Scottish First Division - but more importantly, far more importantly, they had beaten Celtic, at Parkhead, in the Scottish Cup - the biggest upset in the competition since Rangers had fallen to Berwick 33 years before.
Non-league side Dagenham were penniless and languishing in the
Isthmian League 10 years ago, their glory years of reaching FA Trophy finals and FA Cup third rounds long gone.
Their neighbours Redbridge Forest, themselves a merger of Walthamstow Avenue and Leytonstone and Ilford, had reached the Conference but had sold their ground - so the two clubs got together.
A Conference club they remain - but a successful one, currently sitting third in the table and with no financial problems.
Earlier this year they came within seconds of knocking Premiership Charlton out of the FA Cup.
Dreaded phrase
Of course, those are the happier tales, where clubs not only kept their existing support but built on that.
The opposite can just as easily come true.
Just one mention of the dreaded phrase 'Thames Valley Royals' is enough to give Oxford United and Reading fans heart palpitations.
Original fat-cat chairman Robert Maxwell smelt the sweet smell of cash when, on 16 April 1983, he bought a controlling stake in Reading.
Maxwell, already chairman at Oxford, soon unveiled the grand plan behind his purchase: he wanted to merge the two clubs into one, the hideously-monikered Royals, to play in the south Oxfordshire town of Didcot.
Famous old clubs
Fan protests saw that calamity averted.
Other clubs in other sports have not been so lucky.
In June 1999 London Irish Holdings Ltd announced the formation of a new company, Irish, Scottish, Richmond Ltd, the result of a union between three famous old rugby clubs - Richmond, London Irish and London Scottish.
The Irish proclaimed it as the first of a new generation of superclubs, saying the squad would consist of players from all three teams and that the new club would reflect the traditions of all three.
In reality there was no real merger. Richmond and London Scottish were killed off as professional clubs.
Rugby's other code has also seen its own merger 'mare.
Huddersfield Giants, having been anything but colossi in their brief Super League history, decided on a merger with Sheffield Eagles in 1999.
At the time the Eagles were the toast of League, having won the Challenge Cup Final against red-hot favourites Wigan in May 1998.
It took just one season for the union to fall apart. Fans and players alike were utterly uninspired by a clunky new name, and the clubs came apart again before the start of this season.
It had been an unqualified flop.
Huddersfield remain Super League whipping-boys, while Sheffield have to content themselves with a place in the glamour-free Northern Ford Premiership.
Significant obstacle
QPR and Wimbledon fans may be right in saying their clubs have little in common, no foundation of shared history on which to build anew.
But another example from north of the border suggests that this may not be a significant obstacle.
The majority of fans in Dundee are in tentative favour of a merger between the city's two clubs, according to a recent survey by the local newspaper.
And these are two clubs with a far longer and more bitter rivalry than anything the two London sides can produce.
Traditionally, Dundee were the club of those whose fortunes had been made in the jute business - while United fans were descendants of men who worked in the mills.
If that hurdle can be cleared, who knows what could be in store at Loftus Road and Selhurst Park?