Giving diseases to players, sounds like so much fun until you do it. Tons of fun rules seem to go that way, rules designed to maul injure or disfigure some ones character. I've found crippling handicaps being handed out, not really a game enhancer. GURPS Goblins, the whole supplement is built around forcing your players into making characters who are physically and emotionally crippled. Drunks too, every character is a raging alcoholic. Sure, you get to talk in a cockney accent, rob, steal and maul indiscriminately, but most normal things will send you running due to all of your phobias. "It's dark out? Nope, can't go out today, got a fear of that. Plus, we have to cross the Thames, can't do that, afraid of water. Guess I'll just sit here and get drunk, roll on the inebriation table a few times." To top that off, every month on the date of your birthday, you have to roll for a new disease. Super fun, ran it twice.