There has been one finale in particular that is simply unforgettable - though perhaps won't be high up on the list of Leinster fans' favourite memories.
Leinster 30 Ospreys 31 - 2012
The stage was set for Wales and Ospreys legend Shane Williams to bow out in style in his final-ever appearance for the Welsh region.
That, however, looked a pipe dream heading into half-time as an irrepressible Leinster carved out a 17-9 lead - the type of lead that the boys in blue very rarely give up at the RDS.
Sean Cronin and Isa Nacewa - the eventual man of the match - put the Leinstermen in the box seat while three Dan Biggar penalties just about kept Ospreys in touch.
But what happened in the second half will go down in Ospreys folklore. After storming out of the blocks, Ashley Beck collected a fine Joe Bearman offload then raced over and Biggar's conversion cut the deficit to one.
The next scores would come via Sexton's boot as Leinster extended their advantage to seven points - through crucially still within a score of Ospreys' sights.
Cometh the hour, cometh the man as with 20 minutes to go, Williams brushed off the attentions of Eoin Reddan to speed into the corner. But Biggar's missed touchline conversion meant the chance for parity was lost.
And it looked as if it was beginning to slip away from the Ospreys again when Nacewa - despite a loose Sexton pass - was quickest into action and his fly-half then converted the try.
With Nathan White sent to the sin-bin the tide turned for good, though it was work to be done even after Biggar's penalty sliced Leinster's lead to five.
Who else to the rescue but Williams, as he somehow contorted his way over the line despite Rob Kearney hanging off him for dear life.
It should neither be forgotten that Wales fly-half Biggar, just 22 at the time, made the pressure conversion to wrench the title from Leinster's grasp with two minutes left to play.
Shane Williams scoots over for his first try
Ulster 18 Leinster 24 - 2013
With three consecutive final defeats in the previous three years, the thought of another defeat was simply unpalatable for Leinster.
Ultimately they got in front early on at the Kingspan Stadium and never let their advantage go, though this final was not without its hearts-in-mouths moment.
A perfectly-executed lineout drive brought up a try within the first three minutes - by Shane Jennings' hand - and Sexton not only added the conversion but a penalty moments later.
It was one-way traffic from then on as Ulster pounded at the Leinster defence, and Robbie Diack also fumbled with the try-line gaping - a mistake that would prove costly.
Ulster eventually got on the board through two Ruan Pienaar penalties but Leinster had the last word of the half through Sexton - 13-6 the scoreline read.
Sexton and Pienaar traded penalties to open up the second 40 before both sides were reduced to 14 men due to sin-binnings for Diack and Nacewa.
And the hosts were coping the better with a man short, as Pienaar's metronomic boot hauled the deficit back to within four points.
Leinster may have bent but they did not break and restored to their full complement, forward grunt again saw them sniff out the try-line through Ireland No.8 Jamie Heaslip - though Sexton missed the conversion.
That score hardly had Leinster home and dry as a perfect Pienaar slotted his sixth penalty of the afternoon before Ulster camped in their opponents' 22.
Leinster fans held their breath as the home side knocked on at the crucial moment, which allowed the boys in blue to wind the clock down and banish some painful memories.
Jamie Heaslip muscles his way over
Leinster 24 Munster 20 - 2001
Going back to when it all began, a more thrilling finale to the Celtic League's inaugural season could never have been dreamed up.
It had everything - though some may have been worried that it would descend into a one-sided affair after Eric Miller was sent off for Leinster in the first half.
Anthony Foley's early try - which had been created following superb work from Rob Henderson - gave Munster the advantage before Miller lashed out to earn his marching orders.
And when John O'Neill touched down just before the end of the first half, the Munstermen headed in 12-6 to the good.
But Shane Horgan, who was eventually awarded man of the match, inspired Leinster after the break and Nathan Spooner's boot reduced the arrears to three points.
Gordon D'Arcy then linked up with Horgan to cross in the 66th minute and put Leinster ahead for the first time - and Spooner's conversion made it a four-point lead.
Within five minutes Brian O'Driscoll's chip ahead allowed Horgan to score himself and with that, despite a late Munster fightback - Anthony Horgan responding in vain - Leinster saw out a sensational 24-20 victory.
Shane Horgan clings on for dear life and scores for Leinster
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