Hush

Hush is an anonymizing overlay for HTTP browsing, similar in spirit to Crowds , but offers much better scalability at the cost of some anonymity. You can download the code here. Please contact me for any questions.
Instructions on installation and usage

The code is based on the Crowds code. It is in perl, and requires the MD5, SHA1, HMAC_SHA1 modules to be installed (the modules are called Digest:SHA1, etc). To run the code, change the configuration file first, and then run the code. The config file is of the following format:

cookies=1
gateway=128.32.39.124
gatewayport=9000
jport=9000
commit=1
verbose=0
firewall=0
degree=4
maxdegree=10
pf=0.25

The "gateway" and "gateway port" refer to some machine that is already part of the Hush overlay, the "jport" is the port on the local machine run. The "degree" refers to the number of overlay neighbhors you wish to have, and "maxdegree" says how much load you can take. "pf" is a number between 0 and 1 that indicates the desired anoymity level: lower this value, greater the anonymity.

After setting the configuration file, run "perl anon.pl [port]". The port is optional, and overrides the jport parameter in the configuration file. Then set your browser proxy to the port on which anon.pl is running, and start browsing. For more detailed instructions on the other parameters, please refer the Crowds page.

Note: Right now, there is no permanent gateway. For playing around with the code yourself, set the gateway to yourself (eg: 127.0.0.1:9000), start the anon.pl code on the same port, and you can run other nodes using this one as the gateway.