Could someone give a quick rundown on the available solutions?

For starters, is it possible for two people running incognito to communicate securely and anonymously? can it even be detected that they are communicating at all?

How can this be accomplished simply for typing? by running Instant Messengers through Tor?

how can this be accomplished with voice to voice communication? this is a far harder task seeing as Tor network will be far too slow for real-time voice communication for most users. Some sort of push to talk system would maybe be necessary where straight away you can detect that the other person is engaged in speaking (because his spacebar is pushed down and that is relayed to you so you have a flashing light) and you will just have to wait a few seconds for all of the voice data to compress and stream before you can hear it.

has anyone thought about this? what is the current state-of-the-art?

also does there exist something like an anonymous noticeboard for sticking anonymous messages, that will be preserved at least for a few months?

thanks,

Sy

You can run any TCP/IP application through an encrypted SSH tunnel, which will prevent it from being eavesdropped.

Though I don't see how two people could have anonymous voice communication... Seems sort of like a paradox, why would you talk one-on-one with a person if you don't know who they are?

It is possible. Since everything in Incognito will go through Tor you'll get anonymity using Pidgin and any of the protocols it supports (IRC, XMPP/Jabber, ICQ, MSN) -- just remember to register a new account/create a new nickname for this purpose. You'll get end-to-end encryption using Pidgin's Off-The-Record messaging plugin (OTR). It's mentioned in the walkthrough.

In the 2009.0 beta there's a VoiP client called Twinkle which supports a number of end-to-end encrypted protocols (SRTP, ZRTP).

I'm not sure exacly what you want here, but services like pastebin might suffice. Of course, the message will be public, but you can easily encrypt it with you PGP key using Firefox' FireGPG extension which is installed per default.

Pidgin doesn't work anymore with ICQ and YAHOO! The version is way too old!