We start with Bryan 'Pop' Robson, who became West Ham United's record signing in 1971 when he cost the East Londoners £120,000 from Newcastle - where he had scored 82 goals in 206 games.
He scored on his debut against Nottingham Forest, and it was a sign of things to come as he ended up being the club's top scorer in two of his three seasons at Upton Park.
A move back to the North East followed with Sunderland before Robson returned to the Boleyn Ground in 1976. He would stay for another three years and in total scored 104 goals in 254 games for the Hammers.
Next up is an England legend who enjoyed spells with both the Magpies and the Hammers in his career, Stuart Pearce.
'Psycho', as he was affectionately known throughout his career, played 37 times for Newcastle between 1997 and 1999, scoring once in a Champions League tie against Dynamo Kiev.
After falling out of favour when Ruud Gullit took over on Tyneside, Pearce went on to join the Hammers, where he made 50 appearances in all competitions, scoring three goals.
He was named the club's Hammer of the Year in 2001 and secured cult hero status by trying to play on with a severely broken leg in a match against Watford.
Pearce now works as a football pundit after being sacked as manager of Nottingham Forest back in February.
On signing Paul Kitson from Newcastle in 1997, West Ham were fighting against relegation from the Premier League.
Hammers assistant manager at the time, Frank Lampard Snr, likened him to Pop Robson before him, saying: "The last man we signed from Newcastle was Bryan 'Pop' Robson in the 1970s and Paul has the same qualities. He is quick, sharp and has good physical attributes."
Kitson had scored 10 goals in 36 games for the Magpies and went on to forge what is still arguably the club's finest strikeforce since the Tony Cottee/Frank McAvennie partnership of the 1980s as he linked up with John Hartson to save Harry Redknapp's side from the drop.
Kitson stayed in East London for five years, scoring 18 goals in 63 games before leaving for Brighton in 2002.
Probably the least well known of the players featured, Wayne Quinn joined Newcastle from Sheffield United for £800,000 in 2001.
After a difficult time at the club he was loaned back out to Sheffield United and then West Ham, who were seeking promotion back to the Premier League under Alan Pardew. He was later released in 2004 after just 22 games for the Hammers.
He then failed to find another professional club and now, aged 38, finds himself as the player-manager of South Western Premier League Division One West club Mousehole AFC.
Next up is a man that needs no introduction, Craig Bellamy. One of football's original bad boys, Bellamy shot to Premier League prominence both on and off the pitch at Newcastle.
He scored 28 goals in 93 games but his time there was marred by a public spat with the manager Graeme Souness, which resulted in a loan move to Celtic before a permanent transfer to Blackburn Rovers.
Bellamy completed a move to West Ham from Liverpool for a fee of £7.5 million in 2007 under Alan Curbishley. He went on to play just 24 games in two years due to injuries, scoring seven goals, but was sold to Manchester City in 2009 for £14 million.
The last two players featured are both plying their trade with West Ham after spells on Tyneside. Kevin Nolan, the Hammers skipper for the last four years, and his good friend Andy Carroll - a product of Newcastle's youth system - were both signed by Sam Allardyce as the Hammers reestablished themselves as a Premier League force.
Carroll's time in Newcastle - where he scored a total of 31 goals in 80 games - was marred by off the field problems. But on it, his and Nolan's goals helped the club bounce back to the top-flight at the first time of asking following relegation into the Championship.
The goals continued to flow as the duo forged a formidable partnership until Carroll was sold to Liverpool for a record £35 million fee. Nolan ended up with 29 goals in 85 matches before moving to West Ham for £5million in 2011.
Their paths would cross again in 2012, though, when Carroll initially went to Upton Park on loan before making the move permanent for around £18 million the summer after.
Injuries have curtailed Carroll's Hammers career restricting him to just 51 games in three years with a return of 14 goals. Nolan, meanwhile, has 30 goals from 136 games for the East Londoners.
Other notable players to have played for both clubs include:
Shaka Hislop, the Trinidad and Tobago goalkeeper who was a firm favourite with both sets of fans.
Scott Parker, a three-time Hammer of the Year and skipper of both clubs. Parker's reputation suffered with some fans, though, when he pushed for a move to West Ham's bitter rivals Tottenham Hotspur after the club's relegation.
Keiron Dyer barely played for West Ham after an injury-ravaged few years at Upton Park following his £6 million signing from the Geordies. He was one of three ex-Newcastle players to join the club under Curbishley alongside Bellamy and Parker for a combined total of £21 million.
Lee Bowyer was a West Ham fan as a child and finally got to play for the club he grew up supporting on leaving Leeds United in 2003. However, his time in East London was interrupted by an ankle injury and when the club was relegated a few months later, he moved on to Newcastle where he scored six goals in 79 games over the next three seasons.
Bowyer would later return to the Hammers, though, this time with slightly more success scoring four goals in 41 games over three years before moving on to Birmingham City.
Demba Ba shot to prominence after his move to East London from German club Hoffenheim, and subsequent goals nearly saved the Hammers from relegation.
He had a release clause and went on to join a former Hammers manager, Alan Pardew, at St James' Park, where he scored 29 goals in just over 50 games to spark a big-money move to Chelsea.