The Pyro's "Coffin Kit" has a note on its side which lists the names of various regular item contributors from the TF2 Emporium's Steam group chat. The top name on the list, "Sexy Robot", is the creator of the "Coffin Kit" item.

There are several unused voicelines that were added during the Love & War update that suggest a feature where the classes make fun of another player's weapon or hat, as well as a number of lines related to trading.

There are unused particle effects with names that relate to the "Conga" taunt. This suggests that the taunt was originally intended to constantly spawn confetti, streamers and fireworks, which are either green or pink.

The sniper rifle "The Classic" is a remake of the sniper rifle found in Team Fortress Classic.

When the 'Meet the Spy' video was released, The Sniper playermodel was updated in the game, adding the scar that the sniper got in the video. Previously, he had no scar on his face. It was never taken off the player model, and still has the scar.

The Stickybomb Launcher bears resemblance to a weapon cut from Half-Life 2, simply named the "Sticky Launcher". Had it been included, it would have functioned in an almost identical manner, except that it would stick to enemies as well as map surfaces. Also, the Stickbomb Launcher was originally supposed to be the Pipebomb Launcher seen in Team Fortress Classic, but it was changed to the Stickybomb Launcher as the Pipebomb Launcher's only difference was that you could detonate the pipebombs with the alt fire key. The model remains in the game.

One of the Scout's taunt attacks, called the Home Run, is a reference to Babe Ruth's famous "Called Shot" where he points to the sky, and hits a home run. The scout repeats this, and proceeds to bat any enemy caught in the swing 25 meters away as stated in the related achievement "Out of the Park".

The weapon Cleaner's Carbine, and the hat Liquidator's Lid both reference the hitman from the French film "Léon: The Professional", who refers to himself as a "cleaner", rather than a hitman. This view of himself also reflects that of the Sniper's, as he always refers to himself as a "Professional" rather than a psychopathic killer everyone sees him as. The description of the Liquidator's lid also alludes to the lead guitarist (The Edge) of the Irish rock band U2, who wears a similar tuque.

During the Love & War update, using a Teleporter can cause a random piece of bread to spawn at the exit. This is a reference to the video "Expiration Date". The chance for bread to spawn from the Teleporter is 1/20, with a hardcoded exception for the Soldier where the chance is a much higher 1/3.

Ludmila is a scrapped unlockable primary weapon for the Heavy. Its appearance was later used for Natascha, and the model is still referred to internally as "c_ludmila".

The P.D.Q. was a scrapped melee weapon for the Engineer that was tested in the Team Fortress 2 Closed Beta. It used the game's Wrench model.
The P.D.Q. does not have the ability to be used to upgrade buildings, and instead increases the Engineer's rate of construction by 150% when hitting the building with this weapon.

A Fire Retardant Suit was a scrapped secondary weapon for the Spy that was available for use in the Team Fortress 2 Closed Beta.
Two variants of the Fire Retardant Suit are known to have been tested. The first Fire Retardant Suit simply reduces incoming fire damage by 90%. The Fire Retardant Suit Beta 2 does not reduce fire damage, but instead grants the wearer complete immunity to the afterburn effect.

The Branding Iron is a scrapped melee weapon for the Pyro. It is an over sized branding iron which bears the initials 'TF' on its head.

The Neon Annihilator's battery has a nod to the Facepunch forums written on it: the texture reads "def2fp", meaning Death to Facepunch. The BLU version was originally intended to say "props2fp", but was changed by Valve, possibly unintentionally.

The weapon was originally supposed to be a chinese lantern, but the idea was dropped at Valve's suggestion since it closely resembled an unused weapon called the "Baleful Beacon".

There are unused sounds for the Rescue Ranger. The sound names imply that at one point during development, the weapon was able to move buildings and to be charged to fire a (probably) more powerful shot. These abilities were presumably removed for balancing reasons.

At the end of the "Meet the Soldier" trailer, there are only 8 heads on the fence. The only head that doesn't appear is the Scout's.

It isn't simply off the screen however, as the 8 heads are all part of a single model file, which shows that the partially obscured head in the video is that of the BLU Soldier.

A Golden Frying Pan weapon was added in The Two Cities update. However, unlike the 19 generic Australium weapons introduced at the same time, the Golden Frying Pan shares an unusual trait with previous rare items made of Australium: enemies killed with it will turn into a golden statue. Whenever earned in a Mann vs. Machine game, a global message is displayed that states the owner's name. Since the update, only a few have been found, with the first one selling on the Steam Marketplace for $5,500.

While wearing the "Magical Mercenary" Hat, the Soldier says "Friendship is magic, Creampuffs" and the Scout says "Friendship is freaking magic". Along with the hat's design, both phrases are references to the show My Little Pony: Friendship is Magic.

The texture for the community-created HazMat Headcase item has a hidden note in the corner, outside the area used by the model. The message reads "Aca ♡ Prim 4evr~", meaning "Sparkwire loves Primrose forever", both of whom are credited with the item's creation.

The "Meet the Medic" class video was originally going to follow the interview format that the previous Meet the Team videos had used.

After a lot of iteration, with different scenes being scrapped for different reasons, the team realized they were putting too much focus on the creation of the Medigun and not the Medic himself. Once they found the right idea, the video came together relatively quickly.