Legends of Zork

From Wikipedia Legends of Zork is a browser-based online game, based on the Zork universe. Players control a recently-fired traveling salesmen for FrobozzCo International, now fighting monsters and solving puzzles for zorkmids (the world's currency). A class, leveling, equipment and skill system give each character unique attributes. Free accounts are given 30 action points per day, but can pay a fee to receive more and other "perks".