Generic themes for projects:

• Adventure / Role Playing Games -- goals, player attributes, puzzles, random outcomes (dice rolls), player evolution
• Sports -- Team competitions, strategy, rules, action set
• Flying -- 3D navigation, tours, goals/discovery
• Driving -- 2.5D navigation, tours, goals, competition
• Shoot 'em Up -- reaction time, pattern recognition, player health
• Beat 'em Up -- reaction time, action selection, interpersonal contact, character design
• Platform (Mario-like) -- puzzles, obstacles, hand-eye skills, exploration
• Puzzle/Strategy -- solve to yield result
• Simulation -- evolution, choices, survival models
• Classic Games -- known rules, boards, implements (cards), strategies