To run I2PSnark from the command line, run "java -jar lib/i2psnark.jar", but to run it with the web UI, run "launch-i2psnark". I2PSnark is GPL'ed software, based on Snark (http://www.klomp.org/) to run on top of I2P (http://www.i2p2.de/) within a webserver (such as the bundled Jetty from http://jetty.mortbay.org/). For more information about I2PSnark, get in touch with the folks at http://forum.i2p2.de/