If you've never tried Pébéo's Vitrea 160 Glass Paints then it's worth checking them out. They are great for decorating a variety of surfaces including cards, ceramics and, of course, glass. You can use them in conjunction with the outliners to keep the colours separate and give a traditional stained glass effect or mix it up a little as in the Vitrea Fusion Card. If painting a heat-resistant surface you can bake the decorated item, once dry, to make it dishwasher proof.
Don't forget, if you've got photos of any glass painted project, do send them in to our Crafter's Gallery (firstname.lastname@example.org) as I'm sure everyone would like to see them!