Skylum's Luminar 3 has made remarkable strides on the way to Luminar 4. The application is less than four years old, yet it offers some delightful surprises. In Short Circuits: If you'd like to be able to create a temporary address that you can provide when you're not quite sure you want to give someone your real address, Mozilla's Firefox Relay may do the job. It's in private beta now. • Remember The Oregon Trail, Zork, PacMan, or M.U.L.E.? If you liked these games in the 1980s, you can give them a second shot right now on any Windows, Mac, or Linux computer. No downloads are involved because they run in a browser window. In Spare Parts (only on the website): Microsoft is experimenting with hydrogen fuel cells for backup power at data centers, and says that they offer advantages over diesel generators. • The Firefighter Safety Research Institute has released a report on a fire at a 2.16 megawatt lithium ion battery energy storage system in Surprise, Arizona. • Twenty years ago: The US Postal Service was thinking about offering email. Just about everyone thought it was a dumb idea, but it might have solved one of today's problems.