A catchy game

I was thinking what makes game catchy. I come to conclusion that addictive game should have something from these :

• Some high-score system, so players can compete with them selfs. This system doesn't have to be made using points, for example in Diablo such high-score system was in form of player's character level. The higher level character was equivalent of higher score. Anyway, addictive game should have some kind of ranking.
• User customizable content. It would be nice if players could make maps for their favorite game or create their own units, in game logos, avatars, or weapons.
• The game should have some elements which make player "involved". Such element could be hero which player controls and can identify with or something what player creates like city (in sim city) or town, base, organization (in any tycoon style games).
• Humor - This is always good, I remember playing Fallout games because of this.
• Rewards - it's good if game rewards player for his efforts. It's connected with high-score system, but this is not the same. I mean, if you play long, your character is stronger, more powerful. Your empire is more significant.

Now the problem is to invent such game ;)