My friend Jon Singer has been experimenting with creating a relatively-cheap, straightforward flashlamp-pumped dye laser. This first-blush version uses caps he bought on eBay. As he refines the design, he hopes to avoid as many commercial components as possible. This proof-of-concept build was attempting to answer the musical question: Is a dozen Joules enough to threshold a dye? Answer: yes.
Jon also recently called me, excited, ’cause he’d managed to get three dyes to oscillate in the same cuvette to create RGB laser light! The guy’s a monster. Half the time, I don’t really understand what he’s talking about, but I always feel smarter for having done so. See his “RGB ‘White’ Dye Laser Light from a Single Cuvette” research report here.