I turn off the LEDs to not waste power when I'm not using it.
Saving watt of power!
Wow, aren't we clever!
If you did the keyboard cover thing twice a day, 5 seconds each time, 365 days a year, it would amount to 60 minutes.
that's $7.25 at minimum wage.. which buys 48Kwh of power
@ 5v 0.5amps USB 2.0, the $7.25 buys you 19,332 hours of continuous keyboard power.
2.2 years of continuous keyboard power.
so... No, the power saving is not significant.