A simple nodejs script that imports an existing YUI module-based project into a Yogi <http://yui.github.com/yogi/>-based tree. It's not perfect--it doesn't remove the existing boilerplate, but it's a start.

yogi-import.js

/*global require,console,process*/
var fs = require("fs.extra"),
  exec = require('child_process').exec,
  path = process.argv[2];

fs.readdirSync(path).forEach(function (name) {
  var loc = path + "/" + name;

  // Is it a directory?
  if ((/^[^\.]/).test(name)) {
    
    fs.lstat(loc, function (err, stats) {
      var jsFile = "/" + name + ".js",
        cssFile = "/" + name + ".css",
        dest = "./src/" + name,
        type,
        cmd;
      
      if (err || !stats.isDirectory()) {
        return;
      }
      
      type = fs.existsSync(loc + jsFile) ? "js" : "css";

      cmd = "yogi init " + name + " --yes --type " + type;

      // create the directory
      exec(cmd, function (error, stdout, stderr) {

        if (error) {
          console.log("yogi error on " +  name + ": " + error);
          return;
        }

        // if it's a JavaScript module
        if ("js" === type) {
          // copy the javascript file into the generated src folder
          fs.unlink(dest + "/js" + jsFile, function (err) {
            if (err) {
              throw err;
            }
            fs.copy(loc + jsFile, dest + "/js" + jsFile, function (err2) {
              if (!err) {
                console.log("copied " + loc + jsFile + " --> " + dest + "/js" + jsFile);
              }
            });
          });
        // otherwise
        } else if ("css" === type) {
          // copy the CSS into the CSS folder
          fs.unlink(dest + "/css" + cssFile, function (err) {
            if (err) {
              throw err;
            }
            fs.copy(loc + cssFile, dest + "/css" + cssFile, function (err) {
              if (!err) {
                console.log("copied " + loc + cssFile + " --> " + dest + "/css" + cssFile);
              }
            });
          });
        }
        // if an assets folder exists
        fs.exists(loc + "/assets", function (exists) {
          if (exists) {
            // copy the contents of the assets into the new assets folder
            fs.copyRecursive(loc + "/assets", dest + "/assets", function (err) {
              if (!err) {
                console.log("copied " + loc + "/assets --> " + dest + "/assets");
              }
            });
          }
        });
      });
      
    });
    
  }
});