Data Dumpster Dive¶

Paper scraps cover a potting bench and spill from a wicker basket beneath it, each one a fragment of somebody's day. Three children pin their findings to a corkboard where a portrait is taking shape beside the headings NAME, ADDRESS and ROUTINE, and a fourth holds up one more scrap. The chalkboard reads DATA DUMPSTER DIVE.

Before the game begins, someone prepares a set of cards representing fragments of a person’s data trail: an email address, a shopping receipt, a username from a forum, a photo with a location tag, a fitness tracker log, a booking confirmation. Scatter these around the room. Players have a few minutes to collect as many as they can, then sit down together and try to piece together who the person is: their name, where they live, what they do, what their daily routines look like.

Taken one by one, none of the cards seems like much. A username is just a username. A receipt tells you where someone shops sometimes. A fitness log tells you when they tend to leave the house. But together, these fragments tell a story that is surprisingly complete. In a well-prepared set of cards, it is usually possible to reconstruct a fairly detailed portrait of the fictional person from only eight or ten fragments.

This is the aggregation problem made physical. The term describes the way that combining individually unremarkable pieces of information can produce something far more revealing than any single piece on its own. It is the reason data brokers are valuable to advertisers: not because any one data point is significant, but because enough of them together build a profile. Understanding this through the experience of actually doing the aggregating can change how people think about what they share online.

It surprises anyone who has ever said “well, it is just a username”.

What you need¶

Twelve cards, and somewhere to scatter them.

The fragments¶

Each says little. Together they are a person.

Fragment	What it shows on its own
a receipt for coffee and a sandwich	somebody ate lunch
a username, greenfinch_82	somebody picked a bird and a year
a gym entry log, Tuesdays and Thursdays, 07:00	somebody exercises early
a train ticket, return, same two stations	somebody commutes
a photo tagged with a postcode	somebody was outdoors
a parcel label, name and street	somebody ordered something
a pharmacy bag, collected monthly	somebody collects a prescription
a library receipt, three books on one subject	somebody is reading up on it
a takeaway menu with a phone number circled	somebody orders from there
a school newsletter with a name underlined	somebody has a child at that school
a card statement line, same shop weekly	somebody shops to a routine
a note of a locker number	somebody keeps something in one

The year in the username and the year on the school newsletter narrow an age. The gym log and the train ticket give the hours the house is empty.

Last reviewed: 2026-07-08.