GURPS Lite includes basic character creation with advantages, disadvantages, skills and equipment, as well as some rules for playing.
People are allowed to make unmodified copies of the document and distribute as they please, as long as they don't charge any more than the cost of reproduction and don't incorporate it into another product.
[1] Unlike the later 4E version, the 3E original included the Magery advantage and rules for casting spells in various mana zones (it is only possible to cast Magic in High Mana settings without Magery).
It also included the 14 basic spells of Create Fire, Daze, Detect Magic, Fireball, Foolishness, Haste, Ignite Fire, Lend Health, Lend Strength, Light, Minor Healing, Shape Fire, Shield and Sleep.
The current version of GURPS Lite is available, free of charge, as a PDF from the Steve Jackson Games website.