For a football team more synonymous with bad personnel decisions than perhaps any in history, smart free-agent pickups are not exactly abundant.
That's why there are only six, and why a couple of them may leave you scratching your head.
Much of that has to do with two of the Lions' longtime general managers. Russ Thomas was often too cheap to sign his own draft picks, much less free agents. The result was a bunch of Hall of Fame AFL players.
Thomas was different than Matt Millen in that Thomas knew what he was doing. Problem is, what he was doing was staunchly refusing to invest any money or effort into the team's success, choosing instead to nickel-and-dime the team to ensure a bottom-line profit.
That formula worked well enough to keep Thomas in his job for 22 years. The Lions missed the playoffs in 19 of those years, largely because of penny-pinching decisions in free agency.
And then there's Matt Millen, who actually wanted the team to do well, but lacked the know-how to make it happen.
Still, despite years and years of mismanagement, and the fact that a vast majority of Lions greats were the result of lucky draft picks, the Lions occasionally got it right in free agency.
At least, these few times, they got it more right than wrong.
This ought to give you a good initial idea of how much the bottom of the barrel is being scraped right now.
Jon Kitna and Scott Mitchell tie on the list for being basically the same person: one-year wonders with no mobility who were otherwise useless.
Both players posted one of the best statistical seasons for a quarterback in Lions history. Mitchell and Kitna both threw for over 4,000 yards in their best Lions seasons: Mitchell in 1995, Kitna in 2007.
Both players have been wiped out of the record books entirely by Matthew Stafford's glowing 2011 season, but at the time, these were some of the greatest quarterback performances the Lions had seen since the 1950s.
And yes, that's actually pretty sad, but at least the Lions were once able to sign free agent quarterbacks and get something from them, even if that was short-term success.
The reason these two players are listed together is because they were signed on the same day, the opening day of the 2010 offseason, and they were both signed for the same reason.
Both were signed because they're solid players, but more importantly, they're vocal team leaders. Both have been instrumental in changing the losing culture in the Lions' locker room, and the result of that change showed up last year as the Lions erased a NFL record number of double-digit deficits.
The reason they're not higher on the list is because of how recently the two were signed. Vanden Bosch and Burleson have played only two seasons in Detroit, and with as much as they may have done for the Lions in those two years, they haven't had the same impact as some of the players on this list who went on to play for several years.
Still, the Lions would likely be a much different team, in many ways, if not for the influences of these team leaders.
Perhaps the third-best personnel move of Matt Millen's career, after drafting Calvin Johnson and Cliff Avril, is signing Dre' Bly.
Was Bly the greatest cornerback of all time? Not at all. He was fast and risky, and made about as many big plays as he gave up.
But wrap your mind around this: Matt Millen signed an All-Pro cornerback. And he actually wasn't an All-Pro until 2003, his first year with the Lions. Bly also made his first of two consecutive Pro Bowls in 2003.
Bly was only in Detroit for four years total, before Millen wrecked all of his goodwill from signing Bly by trading him to Denver for Tatum Bell and George "False Start" Foster.
Still, Bly pretty much fell off the map in Denver, and retired from football in late 2011. So now we can say, with absolute certainty, that the Lions signed Bly for the prime of his career, and then dumped him just as he began to tail off, rather than overpay him in his declining years.
Honestly, when does that ever happen to the Lions?
Okay, so realistically, Erik Kramer belongs in the Jon Kitna/Scott Mitchell category.
Kramer was just another stop-gap QB (actually a CFL player when the Lions took him in) who had all of one good year to help people remember him by.
Difference is, he had something in that one year that no other Lions quarterback does: a win in the NFL playoffs.
Kramer was the Lions' starting quarterback when they won a franchise record 12 games in 1991 and went on to demolish the Dallas Cowboys in the playoffs, 38-6.
Kramer probably won't crack any top QB lists, but he had to have been doing something right for the Lions to have such a successful season with him at the helm.
After all, considering this is the Lions we're talking about, it's hard to complain about getting a 12-4 record and a playoff win out of a quarterback signed from the CFL, even if it was Barry Sanders carrying the team.
Can you imagine a world where Lions fans can't look back fondly on the Night Train Necktie (pictured)?
Well, as much as the Lions like to claim Dick "Night Train" Lane as their own, the fact is he played less than half of his Hall of Fame career with the Lions.
But then, that's exactly what makes him such a great free agent pickup, isn't it?
Lane is still one of the most feared tacklers in NFL history, primarily due to the kinds of hits that would get him thrown out of the league if someone tried them today.
The most famous of his moves, the "Night Train Necktie," was effectively a clothesline combined with a helmet tackle. I can't see that going over very well in today's "don't touch the helmet, anywhere, ever," league.
But at the time, tackling by the head and neck was perfectly legal. In fact, it was partially Lane's lethality at the position that caused the league to start evaluating these hits as a health risk.
Though it wasn't with the Lions, Lane set an NFL record in his 1952 rookie season with 14 interceptions. That record still stands today, 60 years later, even though a season has been expanded from 12 games (in Lane's day) to 16.
The Lions got to be a part of that history when they signed Lane for the last six years of his career. Lane was every bit as good as a Lion as he was a Los Angeles Ram and Chicago Cardinal, and none of those teams will ever forget him.
Oddly enough, the Lions two best free agents of all time were both cornerbacks named Dick who were actually teammates at one time.
Dick LeBeau just barely counts as a free agent signing, but he was. The Cleveland Browns drafted LeBeau out of Ohio State in the fifth round of the 1959 NFL draft, then cut him by the start of the season.
The Lions were all too happy to sign LeBeau as a rookie free agent, and over the next 14 years, he put together a Hall of Fame career. He still leads the Lions in all-time interceptions with 62, and sits third in career interception return yardage with 762.
LeBeau was a great player in his own right, but he also teamed with some of the best ever to play for Detroit. "Night Train" Lane, Yale Lary and Lem Barney were all teammates of LeBeau's at one point or another.
And as if his on-field contributions weren't enough, he started coaching immediately after the end of his playing career in 1972, and has been in the game ever since.
It's a shame the Lions never got to take advantage of LeBeau's coaching prowess, but I bet the Lions aren't as sad about that as the Browns are for not keeping hold of the Hall of Famer in the first place.