Offtopic, but I had no use for desktop files in general, as I launch stuff from the command line, but I finally discovered a wonderful use for them. Steam creates a desktop file for Steam games it installs. Steam itself is...not all that amazing as a launcher. Gives you the last five games launched in a contextual menu from a tray icon, and a list of games you can search through in the client interface after you bring up the window and move to the Library tab. However, you can set up rofi to use desktop files as completions (one sets it up to complete on "drun"), and then rofi can act as your Steam game launcher, which is great. I can just whack a keystroke to invoke rofi, and then type a few characters of the game I want and whack enter, and rofi will prioritize by last-invoked. Really nice not having to slog through the Steam interface.