MultiPath TCP is an extension to TCP to transmit data of a single connection over multiple interfaces simultaneously. (http://datatracker.ietf.org/wg/mptcp)
This allows a better throughput and better resilience in case of link-failures.
We have an implementation of MultiPath TCP in the Linux Kernel.
Visit http://inl.info.ucl.ac.be/mptcp/ to try out and contribute to our open-source project.