New service has started up called LendAround.com. A GREAT idea that allows you to see what movies your friends have in their libraries and setups up a system that allows you to track who has what.
I sent them some of my recommendations.
1) What if I have discs on loan to non-LendAround users?
2) I own the discs but do not have immediate access to it (half my library is 2000 miles away).
3) Custom categories for special DVDs or want lists.
4) Ability to export library and download my collection, reviews and ratings into a CSV file.
GoodReads.com is a good example.