This season, however, we're in the happy position where our loanees - players such as Paul-Jose M'Poku, Tom Carroll, Harry Kane and, before he signed permanently, Andrew Whing - have augmented an already effective squad. So, in tribute to these and other loaness before them, I've compiled a top ten of borrowed talent.
But first a disclaimer. I've only included players who only ever appeared for Orient on loan, rather than those who then went on to sign permanent contracts. Otherwise I could have counted the likes of Steve Castle, Scott McGleish and Ryan Jarvis. Not that Jarvis would have got anywhere near the list, of course.
The list is based on the loanees' impact while at Orient, rather than their overall talent. (So no Gary Hooper, who only played two full games for us.) Also, I haven't really done any proper research or anything, so it's mostly skewed towards the last few seasons and I've probably forgotten someone. Nonetheless, here goes...
10. Jordan Spence (West Ham)
21 games from November 2008 to May 2009
The hole he was filling... The huge crater-sized one next to Tamika Mkandawire in central defence that would otherwise have been filled by Luke Ashworth or a limp lettuce - same difference.
Key contribution... Alongside Mkandawire, the young West Ham loanee provided a touch of class in defence as part of new manager Geraint Williams' rearguard action that saw Orient win nine in 14 games from February 2009, staving off relegation for another year.
Where is he now? After one single appearance for West Ham and another loan spell at Scunthorpe, Spence is now on loan at Bristol City.
9. Luke Summerfield (Plymouth Argyle)
15 games from September to December 2009
The hole he was filling... The one created in midfield previously filled by Jason Demetriou's ego, which had inflated to such gargantuan proportions after one scout from Charlton came to watch him one time, it was about to declare itself an independent state.
Key contribution... Coolly marshalling the midfield, providing the odd bit of creativity and helping Orient turn around an eight-game winless run and pick up a few valuable points in the run-up to Christmas.
Where is he now? Back at Plymouth and facing imminent relegation to League Two.
8. Dean Morgan (Luton Town)
34 games from August 2008 to May 2009
The hole he was filling... Morgan was the left-footed winger that Martin Ling pledged to bring in before the start of the 2008/09 season. Never mind that he was actually right-footed, for the tattooed Luton man could strike a ball better than the rest of the team with either boot. Morgan divided opinion among fans - some hated him, while others despised him. Talented though.
Key contribution... Falling on the floor, crying, pouting, sulking, bottling out of tackles and feigning injury. Oh, and almost single-handedly beating second-placed MK Dons away from home in January.
Where is he now? After short spells at Grays Athletic, MK Dons and Aldershot, Morgan's now helping Chesterfield with their League Two promotion push.
7. Jamal Campbell-Ryce (Charlton Athletic)
19 games from August to November 2002
The hole he was filling... The lack of anyone in midfield or attack with any spark of creativity. Or pace. Or ability. Campbell-Ryce had to compensate for the talent graveyard that was Paul Brush's squad in his only full season in charge of the Os. Carl Hutchings, Lee Thorpe, Scott Canham, Matt Brazier, Ciaran Toner... Read 'em and weep.
Key contribution... Tearing apart the QPR defence - Clark Carlisle in particular - in a satisfying 3-2 League Cup victory for the Os, in which Campbell-Ryce also scored the opening goal.
Where is he now? Playing for Bristol City in the Championship, after spells at Rotherham, Southend and Barnsley.
6. Andros Townsend (Tottenham Hotspur)
26 games from August to December 2009
The hole he was filling... The one created by leaving JJ Melligan on the bench. To be fair, there wasn't that much difference between Melligan and Townsend, save for the fact that the Spurs loanee could actually pass a ball, trap it, dribble, run at pace, put in decent crosses and shoot. The two players were similar in that they were both human beings though.
Key contribution... Scoring this wonder goal against Yeovil in August 2009, in which he ran a full 70 yards past half the opposition team before placing the ball in the net from the edge of the penalty area.
Where is he now? On loan at Millwall, after spells at MK Dons, Ipswich and Watford.
5. Simon Church (Reading)
13 games from February to May 2009
The hole he was filling... The one vacated by Adam Boyd who, presumably sick of his teammates lumping the ball towards his head, rather than to his feet where he was occasionally effective, had given up for the season as he waited for his move back to Hartlepool.
Key contribution... Hitting the winners against Carlisle and Stockport in March, part of a late season run of form that saw Geraint Williams' team escape relegation by the skin of their teeth.
Where is he now? Back at Reading - although not having the best season in front of goal - and with 11 full international caps for Wales to his name.
4. Nicky Adams (Leicester City)
6 games from January to February 2010
The hole he was filling... The one left by departing loanee Andros Townsend that should have been filled by JJ Melligan, if only the Irish midfielder wasn't as out of his depth in League One as a stowaway on a submarine.
Key contribution... Repeatedly beating his man and getting the ball into the box, helping Orient to amass 15 points in the six matches he played. Had a particularly effective game at Charlton, which the Os won 1-0.
Where is he now? Orient fans clamoured for his signing in the summer of 2010 but were probably relieved he went to Brentford and then Rochdale, for each time he's played at Brisbane Road since his departure he's been about useful as Russell Slade's tub of Brylcreem.
3. Paul-Jose M'Poku (Tottenham Hotspur)
26 games from September 2010 to current
The hole he was filling... Not so much a hole, rather the lack of someone with such dribbling ability he can make defenders curl up into a little ball and scream, 'No, please, make it stop.'
Key contribution... Tearing Droylsden apart in the FA Cup 2nd round replay as if he were a rottweiler at an origami convention. Plus a breathtaking winning goal against Oldham at Brisbane Road and a general ability to come off the bench and give the team a bit of Belgian magic.
Where is he now? Happily Paul-Jose is with Orient until the end of the season.
2. Richard Garcia (West Ham United)
21 games from August to November 2000
Key contribution... The Australian formed an effective partnership with Griff that helped Orient to 33 points from their first 18 games of the 2000/01 season. By the time Garcia crocked his knee against Cheltenham in November he'd helped to provide the foundation upon which Orient built their successful push for the play-offs.
Where is he now? Playing for Hull City in the Championship after a couple of seasons in the Premier League. Garcia also has 14 international caps to his name.
1. Kevin Campbell (Arsenal)
16 games from January to April 1989
Key contribution... Goals. Lots of goals. The young Arsenal striker - who turned 19 years old as he joined Orient - hit nine in his 16 games for the club, helping Orient to drag themselves out of the depths of Division Four into the glitz and glamour of Division Three, where enticing fixtures such as Rotherham, Chester City and Mansfield awaited.
Where is he now? Campbell retired from football in 2007 after many seasons climbing all over defenders in the top flight. He now co-owns a security company specialising in protection for wealthy clients.