As I was wandering round the supermarket today, I was struck by the idea for this GURPS perk, so here we are.
We've all seen those films where someone can identify a gun from the sound of its shot, a car from its tracks, or an aircraft from its silhouette. Maybe we know someone who can do that. At least it's likely we know someone who's really good at knowing what bird they've seen or what car went past, even on a moment's glance. Armed forces famously released (maybe still do?) playing cards featuring the silhouettes of friendly and enemy ships or planes to train this very capability. There are still sets like this - I used to love the Heritage ones featuring the natural world.
I thought this very specific trick - knowing what something is, without necessarily having any further insight or any practical application of that knowledge - was a good shot for a perk.
Expert Identification
You've developed a knack for distinguishing a particular category of things, granting you a bonus on rolls to identify them accurately and with increasing specificity.
You can select a specific type of organism, object, substance, or a cultural marker. The bonus ranges from +2 to +4, depending on the scope of the category. Any category can be limited by type, region or era.
Examples: Pet cats, domestic sheep, American cars, early C21st cars, collectible card games, WW1 military aircraft, swords, Chinese architecture, cigarettes, mobile messaging app stickers, 1990s French slang, silent comedies, Japanese makeup patterns, seabirds, sharks, citrus plants, grain, synthetic fabrics, cheese, roses.
There is no prerequisite for this perk; your ability could come from rote memorisation or from a deep knowledge of the subject.
Expert Recognition
Prerequisite: Expert Identification with the chosen type of object or creature.
You're so familiar with your area of expertise that you can recognise individuals as readily as human faces. You can remember and distinguish individual objects or creatures in the same way as recognising a human. Anything that hampers your facial recognition impedes this capability in the same way.
This perk is most suited to categories with individuality, such as animals, castles, vintage cars or rare books. Objects that are mass-produced (like cars or guns) may need further examination and interaction to reveal their individual qualities. The GM determines whether this park is appropriate (or even logically possible).
Note:Even this second perk is a genuine phenomenon, with the brain's facial recognition capabilities expanding to include another category where we're exposed to countless variations on a theme. Farmers can recognise individual animals, and mechanics learn to identify specific vehicles from the details indistinguishable to non-experts.
Examples
Pigeon Fancier
You have an expert eye for the many varieties of doves and pigeons. You gain a +4 bonus on rolls to identify domestic and feral doves and pigeons of all kinds.
Dinosaurophile
You delight in dinosaurs of all kinds, and have spent hundreds of hours poring over illustrations. You gain a +4 bonus on rolls to identify dinosaurs, pteradons, and similar creatures that appear in dinosaur books.
(this is, as the text suggests, intended for a game NOT set in a dinosaur era! In a game where dinosaurs are ubiquitous, reduce the bonus or narrow the focus)
Shepherd's Eye
Extensive experience makes it trivial for you to recognise every member of your flocks. You gain a +4 bonus on rolls to distinguish breeds of domestic sheep, and you can identify individual sheep as easily as humans.
(this is just both perks combined because domestic sheep are a pretty niche group)
Firearm Connoisseur
You've seen countless firearms of all kinds, and understand their idiosyncrasies. You gain a +2 bonus on rolls to identify firearms. You can recognise an individual weapon if you've spent enough time using or observing it to gain familiarity (p. B169) - for example, a companion's trusty revolver, or your battered lasrifle from your days in the Corps - or have the Photographic Memory advantage.
Hun Spotter
All that time playing cards wasn't wasted; you've memorised the outlines of every plane you might encounter. You gain a +4 bonus on rolls to identify WW1 military aircraft.