No extra plug-ins needed. Just what comes with Photoshop. This tutorials runs through the basics of creating a space scene without any extra plug-ins like Flaming Pear's Glitterato (which is an excellent plug-in, btw). This tutorial was originally done as a class assignment and is technically a work-in-progress. I'll be adding example images as soon as I have time to make a few as well as new tips and tricks that I may come up with in the process.