Tip jar
A tip jar is a spawned object that appears in The Sims games. It's commonly depicted as a spherical glass jar with a green Simoleon symbol on a piece of faded paper taped to it. When a Sim engages in a certain activity, they will set this object down next to them before they start the activity. Sometimes the option to set down a jar is delineated by the words "For Tips" being a part of the command; other times using the jar is the default. Other Sims passing by will come up to the performing Sim, watch briefly, and then drop money in the jar. How much money was dropped can be discerned by how much money the donating Sim lost, however the performing Sim won't have the money added to their wallet until they pick up the jar. How much money a watching NPC or non-controllable Sim will donate is usually determined by how skilled the performing Sim is at whatever they're doing. When a Sim finishes performing, they will go over to the jar and collect their earnings. Depending on how much money they amassed, the Sim will go through either a happy, neutral, or disappointed animation, then put the jar away. Activities involving tip jars are usually indefinite and only end when the player cancels that action, or if the Sim becomes too unhappy to continue.
The Sims 2
University
Playing an Instrument
Three new musical instruments are added: the guitar, the bass, and the drum set. Each of these offer the options "Practice" and "Perform..."., with "Perform..." being the option to play for tips. Additionally, the expansion pack adds a "Perform..." option to the available interactions for the piano from The Sims 2 base game. These instruments can be played together using the "Join" interaction, but all playing Sims will have their own jars and collect their tips separately.
Sims may "Perform..." autonomously, unless a mod which prevents this is used.
Freestyle Rapping
Sims can "Freestyle" or "Freestyle For Tips" at any point by selecting the Sim you want to freestyle.
Seasons
As with the University instruments, Sims can use The Rock Hammer to "Perform...".
Bon Voyage
On Twikkii Island there is the Fire Dancer NPC who will stop their performance to teach your Sim fire dancing as a secret skill. While the NPC does not themselves collect tips, after learning to fire dance, your Sim will have the option to fire dance for tips. NPC Fire Dancers can also be spawned at the community lots of base neighborhoods if the lot is customized to include a fire dancer mat.
FreeTime
As with other instruments in the game, Sims can play the violin for tips, though the interaction is labeled "Play For Tips" instead of "Perform..." . If FreeTime is not patched, a glitch will cause the tip jar to make the tile it is placed on unusable.
Apartment Life
Break Dancing
Break dancing functions almost identically to fire dancing, only with a different NPC found in the base neighborhood. NPC break dancers will spawn wherever a cardboard break dancing mat is placed on a community lot.
Human Statue
The Human Statue will have a tip jar. Unlike other activities for which tip jars appear, this one can only be performed by the NPCs spawned by the Poised Podium by Performance Arts. Playable Sims can only donate to a human statue's tip jar.
The Sims 3
When your sim reaches Level 5 of guitar skill, they will be able to "Play For Tips". In this case, the sim does not use the standard tip jar to collect simoleons, but rather money is deposited in an open guitar case. The guitar case serves an identical function to the tip jar, however.
World Adventures
Sims can purchase a snake charming basket at the Al Simhara marketplace. Sims have the option to snake charm for tips. Similar to the guitar case, the lid of the basket replaces the typical glass jar as the object tips are deposited into.
Late Night
Expansion pack reintroduces the piano, bass, and drum set as ways to collect tips. Sims also can play their instrument for tips in the subway, which tends to produce more money, but also runs the risk of being mugged.
Pets
After teaching a dog multiple tricks, owners will have the option to put on a "Trick Exhibition" by selecting their dog.
Showtime
All three of the careers introduced in Showtime, Singer, Acrobat, and Magician, feature collecting tips by publicly performing as a mechanic of advancing through the career path. This starts as early as Level 1 for all three careers.
University Life
Starting at Level 2 of the street art skill, graffiti artists can put out a tip jar and collect tips while painting.
Into the Future
The Laser Rhythm-a-con is introduced as a new instrument with its respective skill set, and therefore it can also be used to collect tips for any sim with a skill level of 5 or higher.
Store Content
The Duke of Bows Renaissance Faire venue reintroduces the violin. However, the violin cannot be played for tips in the subway station.