1. In everyday situations it does work well. I know it's an odd example, but if I am out with some friend for dinner I pay if I know that he/she is broke at the moment or earns less money than I do. They don't have to ask and don't have to return the favor.
2. I have one example from the animal world. When wildebeests are crowded and for example a lion attacks, then the crazy selfless wildebeests try to get between the hunter and the victim to protect the victim. In other words, they offer themselves as victims to the lion, so that the other wildebeest can survive.
The funny thing about it is that a lion wouldn't attack a lonesome wildebeet, because they are to strong for the lion normally.
Another negative form would be persuaded altruism. That's just a thought by myself, but for example if a commander tells his soldiers to die for their country for the higher good and in fact they just fight to the benefit of huge companies or single dictatorships or fundamentalistic groups or noone in the end...
3. I would say that there is moral based altruism, sympathy based altruism and rational altruism. But hey, I'm no expert.^^
4. Maybe honesty?...^^
5. I would say no and I would pin it on the human nature in general to divide things into good or bad. Altruism is just another victim of that form.
I hope I could help you a bit...
