The fifth-tier side held their own at Carrow Road to book a place in the last 16. In the process, they became the first non-league team since Sutton United in 1989 to knock out a Premier League outfit.
Also, in the fourth round, League One side Milton Keynes Dons thrashed Premier League's QPR 4-2. The result ended a promising start to Harry Redknapp's time at Loftus Road.
Both results proved that underdogs, in the heat of competition, can seize the opportunity to progress. It is what the FA Cup is all about.
When you consider their recent history, such results and cup runs are a welcome return. Frustrations in their respective league campaigns can be subverted and inspired by sensational triumphs.
Luton Town's demise was heartbreaking. As a side who originally signed up for the Premiership, they found themselves relegated from the league in 2009 after three consecutive drops.
The last of these was the biggest pill to swallow for the Hatters. A 30-point deduction for financial irregularities saw Luton demoted, even after they tried valiantly to overcome such an extortionate deficit. It was a punishment their fans and players did not deserve.
After suffering that indignity, they have found themselves stuck in the Football Conference after multiple promotion bids stalled via playoff defeats or end of season slumps.
Then you have the MK Dons, a team born out of controversy, who have remained rooted to League One football under similar circumstances. Three playoff defeats in four seasons has been the excruciating outcome of hopeful seasons.
This season, they have come close to chasing automatic promotion, however three defeats in their last six games has seen them drop to eighth in the table. They are seemingly only playoff hopefuls once more.
Yet you can't help but feel that for Luton and MK Dons, their ambitions in the league need to remain a primary focus. By currently standing in positions outside of playoff qualification, a good run of form is required to provide at least the opportunity to gain promotion.
As both have knocked on the door in multiple recent seasons, there needs to be that extra push to gain the desired outcome. Promotion can come into fruition for both if they use their incredible exploits in the FA Cup to inspire results.
One question needs to be considered. What would be the point of defeating Premier League sides if they cannot triumph over the lesser-able squads around them? It would only serve as another year where the main goals and objectives for the clubs are not met.
What awaits Luton and MK Dons in the FA Cup remains to be seen. Luton Town will certainly relish the idea of an away fixture against one of the big boys. MK Dons manager Karl Robinson would surely love a fixture against his home team Liverpool. Maybe even a tie between the two neighbours could provide a highlight of the fifth round.
Whatever the case may be, both sides need to use the momentum and cash incentive from their cup campaigns to boost their league ambitions. Should both achieve the long-awaited promotions, then their seasons can fully be determined as a riveting success.