Okay let's see...
Swap from the heart. My take on it (I've never participated, for whatever reason

) is that you post a list of your "wants". Then people scan the lists and if they have something on your list they send it to you. There's no "matching" or certain number of packages you have to send out, you're just sharing 'from your heart'.
The swaps ~ You sign up and send in items in multiples of 5, with 15 being the max. You can make whatever you want. There's a kid swap and an adult swap. You send a box with all of your stuff in it to the mama(s) who "sorts". In a few weeks, you get a box back chalk full of stuff (in the amount that you originally sent in) from other mamas.
I'm not explaining that one well... LOL