Hi!
I discovered this new addon for Firefox today called Convergence.
It serves as an alternative to using Certificate Authorities to verify HTTPS connections, which opens up for self-signed certificates as well.
It's developed by Moxie Marlinspike and he explains it here:
https://www.youtube.com/watch?v=Z7Wl2FW2TcA
Check it out and say what you think!