get the dependencies:

go get code.google.com/p/go.crypto/ssh
go get github.com/syndtr/goleveldb

then go build and have fun

whisper generate to generate a key
whisper listen to run the server
whisper --key $keyfile --nick $nick dial to run the client

In the client:

notes/create $title to create a note
notes/list to list the notes you have created
notes/get $id to get a note by id

msg/send $recipient send a message to $recipient
msg/list list messages that you have received
msg/get $id to fetch and decrypt a message by id