I love the idea in theory. Most homeschool families have made the sacrifice to live on one income in order to teach their children at home. I'm always looking for used curriculum fairs and online sales forums to try and stretch our school budget (I've given up on ebay--sometimes the bidding for math books goes beyond the price of brand new from the vendor). Here's a way for homeschoolers to become a lending library amongst themselves. The system has tracking features to remind you what you lent to whom and when they're due to return it. You can also sell curriculum that you're finished with without paying listing fees or accumulating enough posts to use some forums. And it's all free to use (at some point down the road there may be enhanced features that require subscriptions or other fees).
Of course, Lobster Network is only as good as the work that's put into it. This can mean adding a lot of your own inventory that you're will to share with others. (Thanks to the Homeschool Crew and my habit of buying things far in advance, I have material that my Schnickelfritz won't get to for years). It also means recruiting friends and other nearby homeschooling families to join the network. I did join a "community" made up of other Homeschool Crew members, but they're located around the world--not to handy to borrow a book from. Currently, my local co-op maintains a Yahoo group and messages get posted there about things people want to buy, sell, or borrow. I've created a Lobster Network community for the co-op but have had a hard sell getting people to do the upfront work of adding their inventory.
As I mentioned before, the Lobster Network is a free service. Why not suggest your local co-op set up a community and begin sharing resources with each other.
You can read what my fellow crewmates think about Lobster Network by clicking here.