I have previously mentioned Mixmaster ont his blog, a great software tool to send anonymous email and also used to post to Usenet groups anonymously, but visiting a website in order to send an anonymous email is not a good idea because your IP will be logged by the site server.
You could use a proxy to get around this, or maybe you just want light anonymity, or you may be using a restricted computer and need to send an urgent untreaceable anonymous email or Usenet message.
That is when a web interface to send anonymous messages through Mixmaster will come in handy.
If you want to run a web interface for the Mixmaster remailer on your server you could use Pyano, recently released (March 2010) and heavily inspired by the mixweb perl script (last updated in 2005) at cotse.net.
Pyano web interface mixmaster remailer for administrators
If you are a simply remailer user and want to send an anonymous message or if you want to see how Pyano works, then visit:
Mattherhorn remailer web interface for users

Send email anonymous
The German Privacy Foundation also has a remailer web interface on its website, although it does not run on Pyano. And in my experience messages get lost far too often. I suspect this is is because by default the web interface uses a fixed chain of five random remailers, it increases security but also the likehood of something happening to message in transit.
With Pyano you can choose how many remailer proxies you want to use and which ones in particular, even entry and exit nodes.
The German Privacy Foundation also runs a tor proxy and a i2P proxy.
German Privacy Foundation remailer web interface for users

