demaniak/i2p
See official i2p docs for a full description of i2p.
You can run this container with something like this:
docker run -d -p 7657:7657 -p 4444:4444 -v /data/:/home/i2p/.i2p/i2psnark/ demaniak/i2p
Use Foxyproxy (or equivalent) for a seamless browsing experience :)
docker pull demaniak/i2p