If someone wants to remember to do something, they'll tie some string around a finger and keep it there until after they've done it. The string can work because seeing the string will make them remember why they put it there. However, one way to play with this trope is for the person to forget anyway and then try to figure out what they tied the string on there for. Likely to be used by Forgetful Jones or an Absent-Minded Professor.
This trope was especially prevalent in the days before computers, but now that computers are portable and do a much better job of reminding you than this old method, this is a mostly Forgotten Trope.
- An episode of Ranma ½ involves Akane helping Ryoga study so he can take a test and obtain his high school diploma (his absurd amounts of No Sense of Direction, obsession with getting Ranma (which made him wander the world) and being Book Dumb all conspired against him), but being so obsessed with clobbering Ranma and the fact Ranma is constantly pestering him because he's spending time with Akane, the poor girl forces him to promise not to fight and ties a neckerchief around his hand (a Japanese version of this trope) as a reminder. At the end of the episode in a moment that makes Ryoga burst out in Manly Tears, he decides he's too dumb and vengeance-obsessed to be able to keep his promise and follow through with what he wanted, takes off the kerchief, and wanders away.
- Used in a short Chuck Billy story in Monica's Gang (pictured above). It starts with Chuck failing to remember why he tied a string around his finger in the first place, spending the whole day asking people if they had anything to do with it. He finally remembers what he had to do during bedtime, which was to save his best friend, who was in a Literal Cliffhanger the entire time.
- In House of Many Ways, Peter needs to tie different colours of string to his fingers because he can't remember left from right. Taken Up to Eleven when he appears with several strings around almost all of his fingers in order to navigate the titular House.
- In Don't Forget the Oatmeal, a Sesame Street book, Ernie writes down a shopping list for his and Bert's trip to the supermarket, but since he forgets to write down "Oatmeal", Bert ties a string around his finger to help him remember. Cookie Monster goes to the supermarket around the same time as Ernie and Bert due it having a big sale on cookies. When Cookie reaches the cookie aisle, he eats every cookie in sight, making a huge mess of the store. Ernie and Bert help Cookie clean up and remind him to pay for the cookies he had broken and eaten, and when they arrive home, Bert still has the string around his finger, realizing that he and Ernie forgot to buy the oatmeal.
- Referenced in Summer Knight, the fourth Dresden Files book. To protect Murphy from a magical fog that causes forgetfulness, Harry casts a protective charm using a string tied around her finger as the focus, because of its symbolic association with memory.
- In the Scaredy Squirrel book "Scaredy Squirrel at Night", it lists the symptoms of sleep deprivation. One of them is forgetfulness, which is illustrated with a picture of Scaredy with a string around a digit of his paw.
- In the young children's book Aren't You Forgetting Something, Fiona?, Fiona the elephant has a poor memory, unlike the rest of her elephant family. When she signs up for a new exercise class, she ties a string around her trunk to remember where she's going, but forgets anyway. Thinking the string is a festive ribbon for a party, she buys a gift for her best friend, whose birthday isn't for another month. When she finally gets to the exercise class, the string makes a useful headband.
- In the Mork & Mindy episode "Mork Runs Down", Mork ties a string around his neck and says that it's his species' way of remembering things. Mindy says that humans tie it around their fingers.
Mork: That's how we used to punish cattle rustlers.
- There was an episode of Mystery Science Theater 3000 where TV's Frank tries to remember who Merritt Stone is and he has strings all over his fingers.
- The Cheers episode where Cliff went into the hospital had the gang miss a chance to visit him. Sam was busy and Norm claimed to feel nauseous when he entered a hospital. Woody, on the other hand, tied a string around his finger to remember and forgot why he tied it. However, we never find out what he tied the other string for.
- A Bert and Ernie sketch on Sesame Street has Bert arriving home to find that Ernie has string tied around all ten of his fingers. Pointing at the first finger, Bert asks what the string on that finger is for. Ernie replies that it is to remind that he has a string on the next finger. Bert then asks him what that string is for, and Ernie says it is to remind him he has a string on the next finger. This proceeds through all of Ernie's fingers until they reach the last one. When a very exasperated Bert asks him what that string is for, Ernie says it is to remind him to buy more string.
- In the The Book of Pooh episode, "Brain Drain", Eeyore has a string tied to his hoof to help him remember something, but he can't remember what it was. Eeyore's friends believe that Eeyore has a Brain Drain, and do everything in their grasp to jog his memory. At the end of the episode, Eeyore looks at the string, and remembers that he tied it to his hoof to help him remind Rabbit to pick his strawberries.
- In "It's All In Your Head" from Bear in the Big Blue House, Bear has a bunch of these. One is to remind him to tell the kids of the Big Blue House that they're going to the fair, another is to remember to pack snacks, another to get a basket to put them in, and one to remember to clean up the house before they leave.
- In The Navy Lark Seaman "Fatso" Johnson once went around for an episode with a bit of string tied around his finger, unfortunately he couldn't remember tying it there so all it did was remind him he had forgotten something (at the end of the episode it was revealed: It was to remind him to buy string).
- Parodied in Kingdom of Loathing with the "invisible string" item — using it ties it around your character's finger, which the game admits "would probably remind you to do something if you could see it".
- Jade Harley of Homestuck ties several colored strings around her fingers, each of which reminds her of a different thing. She removes most of them much later when the absurdity of SBURB makes them pointless.
- The mascot for the ReminderFox browser add-in for Mozilla Firefox is a fox with a string tied around its finger.
- The Google Keep app's reminder feature has an icon of a finger with a string tied like a figure eight loop.
- The Simpsons:
- At the beginning of "Moe'N'a Lisa", Homer wakes up to find a string around his finger, among other reminders that he has to remember something. To his annoyance, Marge tells the family that they're going to see Grampa compete in the Senior Olympics. But actually, Homer promised Moe he'd go fishing with him.
- Subverted in the Simpsons episode "Brother's Little Helper"; Homer is supposed to be looking for Bart (who's gone insane after taking an experimental ADD medication) but is instead at Moe's. When Marge confronts him, he tells Marge "I'm on top of it" and shows a string tied to his finger, thus implying that it's a reminder string. It's revealed as being a really long string with the other end attached to a Box-and-Stick Trap with a jar of Bart's medication underneath.
- In the TaleSpin episode, "A Jolly Molly Christmas", when Molly breaks her last candy cane, Baloo tries to cheer her up by telling her about the Peppermint Fairy, who leaves new candy canes in place of old ones under childrens' pillows. He ties a string around his finger to help him remember to put a new candy cane under Molly's pillow, but the next morning, he sees the string and realizes he forgot. When he tries to put the new candy cane under Molly's pillow, Molly awakens and accuses Baloo of lying to her.
- In the The Flintstones episode Dino Disappears, Wilma made Fred wear a string on his finger to remember to get a present for Dino; however, he forgets who he was supposed to buy a present for, so he instead buys toys for Pebbles, causing Dino to run away.
- In the Max and Ruby episode "Max Remembers", Ruby sees a string tied on Max's finger and assumes that he needs to remember something. She spends the episode trying to help him remember it, only to discover that the string was actually for his yo-yo.
- In "Don't Lose It, Lilly" from Timothy Goes to School, Forgetful Jones Lilly has one on her finger because Miss Jenkins, the teacher, says that it'll help her remember where she put her things. However, when Charles asks her if it works, she admits in hasn't yet. Later in the episode, as she and Charles are being drenched by a rainstorm, she remembers that it was to remind her to bring her umbrella.
Charles: (ears dropping) Good remembering, Lilly.