I've posted a how-to guide for using Freenet anonymously via Tor, with full opennet connectivity, at <http://dbshmc5frbchaum2.onion/Freenet-OnionCat.html>. Basically, the Freenet node is a VM with no public IP address. It reaches opennet peers through a clearnet proxy VPS, linked via Tor/OnionCat. It can also reach peers directly at OnionCat IPv6 addresses.