toss this in your ~/.caprc, then `cap cowboy staging deploy`. Use carefully.

.caprc

namespace :cowboy do
  desc 'Deploy without SCM'
  task :default do
    deploy_stage = fetch(:stage, 'none')
    set :repository,  "."
    set :deploy_via, :copy
    set :scm, :none
    set :stage, deploy_stage
    set :cowboy_deploy, true
    set :copy_exclude, [".git/*", ".svn/*", "log/*", "vendor/bundle/*"]
  end
end

techpickles gemified this up here:

https://github.com/railsmachine/capistrano-cowboy