I'm a bit ignorant about this, but I think the butterfly effect is to do with how complex systems, that have positive as well as negative feedback mechanisms, can produce massive effects from minimal changes.

A buddhist podcast suggested that this means small acts of kindness have the potential to produce enormous benefit.  Well, possibly…  It also emphasized how change is only likely to happen when a system is unstable.

This ties in with the non-zero sum game idea of altruism (see Robert Wright, quoted by the Petri Project).  If I do something for you, it isn't necessarily an equal transaction ("I lose, you gain") because it may be that it is easier for me, or that you were busy with something else.  So potentially, doing things for other people that are relatively straightforward is almost always going to produce an excess of good will!