Ok, 's not really a 'hack' ,but... I've got a beige 1997 G3 MiniTower, that whenever i get the chance, i'll do a quick little mod to. For years i've been l;ooking at the big, translucent, bluish green button on the top (side panel release) and thinking that it really should light up. Well, now it does 
I've put at 12 volt green super bright LED behind it, so, now, whenever the G3 is on, the button on top glows a bright green. I'll post pics as soon as i recharge my digital camera batteries.
G3 Mod.
March 14, 2005 - 6:14pm
#1
G3 Mod.
Wow! A 12 volt LED? It must be like having a spotlight, then.
Yes, a 12 volt led is very bright, however, the translucent plastic of the button diffuses the light enough that it isn't too bright. It is however noticable, and creats a very nice effect, as the riges on the uderside of the plastic creat a kind of ripple pattern in the light.
And it contrasts nicely with the Blue LED i put in place of the stock power on light.
It must be a led with a build in resistor?
nope, the led is rated at a max of 13 volts, and is wired directly into my 12 volt power supply line via a standard Molex connector.
If you did not put a resistor inline with it it must have one built in. Otherwise POOF.
There is a video somewhere of Dr. Bob on the Screensavers. He shows what happens when you don't use a current limiting resistor with an LED.
Here is a write up about it
http://www.g4tv.com/screensavers/features/37123/Add_an_LED_to_Your_Mac.html
I know what happens. The LED works really fantastically well for a few minutes, then it glows red and pretty much 'poof's.
your right, 's got a built in resistor. It's still bright as all heck tho, it looks awsome.
There are LED's available with built in current limiting resistors. Most commonly available for 12V.
I love all the safety crap and terminology that the editors added to that article.
"ALWAYS WEAR EYE PROTECTION!" *sigh*
"The unit of current is the Amp." Couldn't find a better place for this one?
It's been lit up for a week, no problems. Between my superbright blue power LED, and my superdright 12v green LED lighting up the case release button (also goes on and off with power, of course) my G3 is lit up like a christmas tree (at least as much as a beige G# case can be). There's morew to come, i've still got anoter one of these 12v LEDs laying around, wired to a Molex connector, and i'll get pics ass soon as i replace the rechargabe pack for my digital cam (died of old age).