DayTrippers: Core Rules

From Introduction:

In some sun-bleached barn outside Sacramento, CA circa 2099, a group of physicists, shady g-men, grad-students, tourists and an array of amateur explorers and nü-gonzo-revivalist writer-dudes gather around a collection of strange vehicles that resemble lunar landers. Each is painted a garish colour and prepped to "shift" along an angle of slippage into a crazy new plane of existence.

DayTrippers is an OSR RPG approach to a surrealistic science-fiction multiversal milieu, in which an assortment of colorful character classes pilot unique machines into divergent universes to retrieve items of value and bring them back home.