My sister told me about Zwaggle -- a national network of parents who have come together to share kid stuff.
Basically, you receive Zwaggle points (or Zoints) by giving your gently used things to other families, then use those Zoints to obtain "new" things for your family.
They're touting it as 'financially smart' and 'ecologically responsible.'
Now I just need to sort through all of our stuff to get started... I'll let you know how it goes! I know we could really use a double stroller for our nanny to use...