OK, it's not going to turn your Mac into a futuristic Star Trek-style computer, but Time authentically replicates the visual style and feel of the LCARS interface displaying a clock complete with a stopwatch, count down timer and an alarm.
You can choose from 27 different color themes to suit your decor, have the app full screen or windowed and adjust the brightness of the app by dimming the entire interface -- handy if you're using it as a display at night. On the clock front you have the option of 12 or 24 hour display, the option to display the seconds as well as the day and date, which can be displayed as a star date.
All the settings are accessible via large buttons that make up the interface, with each button click emitting a satisfying LCARS sound. Speaking of sounds you have the option of 15 alarm sounds from beeps and chirps to warnings and hailing frequencies, which can be used for both the alarm clock and the count down timer. If all the sounds get a little much for you, there's a button to mute the whole lot too.
Time does what it says on the tin. It gives you a clock in the style of LCARS, and is great for any 24th century Star Trek fans out there. It's free and available from the Mac App Store.