It's a known fact that it's easier to clean things when they're wet. Usually, people will use soapy water, or a chemical cleaning agent. However, soap, cleaning agents, or even water might not be on hand to use in a situation where something must be shined up. That, or the character just doesn't find reaching for one necessary, knowing that they actually always have a liquid conveniently at hand to use -- their own saliva.

This trope might manifest in a character using their saliva to scrub a table or counter until it shines, or to wipe unsightly dirt off someone's face. Doing this may be seen as pretty [[{{Squick}} squicky]] to some, but it can still get the job done all the same.
[[folder:Film - Animated]]
* Mushu tries shining up Disney/{{Mulan}}'s armor to cheer her out of her HeroicBSOD. It doesn't work.
* On ''WesternAnimation/{{Cars}}'', Mater offers to clean off a spot of tar on Lighting [=McQueen's=] hood, and he starts hocking before [=McQueen=] hastily declines.
[[folder:Film - Live Action]]
* Some servants do it with the ''royal crown'' in ''Film/TheMadnessOfKingGeorge''.
* ''Film/SpaceJam'': The WesternAnimation/LooneyTunes gang cleans their gym this way.
* Ragetti does this with his wooden eye a couple times in ''Franchise/PiratesOfTheCaribbean''. Later on, Barbossa gives the thing a ''really'' good slurp and shoves it back into Ragetti's empty socket. The poor man looks terrified.
* Blaze and King Charles II have a bonding moment spitting to shine their leather boots in the French comedy ''{{Film/Delusions of Grandeur}}''.

[[folder:Live Action TV]]
* Jayne of ''{{Series/Firefly}}'' does this with a knife, combining this with LickingTheBlade. This...disconcerts the rest of the crew.
* ''Series/TheBigBangTheory'': Raj uses his spit to clean off dirt from the crotch area of an Comicbook/{{Aquaman}} action figure bought in a garage sale.
* On an episode of ''Series/{{Seinfeld}}'', where George is forced to be a butler for his parents, Frank orders George to shine his shoes, and George spits on the shoe once Frank's back is turned.

* In ''Theatre/AVeryPotterSequel'', Neville begins spit shining Harry's shoes while Dean gives Harry a massage. Ron quickly chases them off and then takes over both duties, [[RuleOfFunny spit shining Harry's back]].

[[folder:Video Games]]
* The bartender in ''VideoGame/MonkeyIsland2LeChucksRevenge'' used his spit to clean the glasses.

[[folder:Western Animation]]
* Done by Hank when he must shine his father's shoes as punishment on an episode of ''WesternAnimation/TheVentureBrothers''.

[[folder:Real Life]]
* Works on shoes.