Okay, so I have a Dell.
Latitude D600
Model NO: PP05L
This is all I know about it.
Let me know if there is something else you need to know.

Okay, so here's the story.
Last night, my computer was working just fine, never had any problems with it. But I was lazy and didn't feel like going to my room to get my charger. So I used a friend's; she also has a Dell. As soon as I plugged the charger into my laptop, it shut off, just completely shut down. I took the charger out and put the computer into my room, didn't really think anything of it. Well a few hours later I went into my room and tried to turn it on, nothing. All that happens when I try to turn it on it the battery light flashes for a split second. I tried to plug my laptop in and turn it on, nothing. I took the charger out and tried it again, nothing. Tried taking the battery out and leaving the charger in, nothing. I don't know what else to try.

Help is MUCH appreciated!

It may be as simple as discharging the Voltage (not exactly done yet)
Have a look here on how to do that: Tutorial: No POST (Power On Self Test)
Please let me know if it helped

I tried it, and it did not work.

The only thing that happened was the battery light flickered like it did before.

ok so you have tried battery on its own (discharge as per guide first)
and power adapter (charger) on its own (discharge as per guide first)

And still no POST ?

I take it that you have continued along with the guide (Ram out; harddrive out etc)

If so, other than "Benchtesting" (in the guide again!) It sounds as though you may have blown the board

What was the voltage on that other adapter (charger) anyway? (and what's the voltage stated on your correct adapter?)

Oh, sorry. I only followed the first set about holding the power but for 30 seconds.
I'm not quite sure how to do the other part.

The other adapter says: Input: AC 100-240V-1.5 A 50-60Hz
And mine says: Input: AC 100-240V-1.5 A 50-60Hz

Thanks.
There should also be another Voltage stated on the output of the adapter (written on it) 9Volts? 30V? something?

kimsland, all dell adaptors have same voltage(19.5v). the difference is only between power of current. of course every dell PSU contains single-wire eeprom, i which the information about this particular PSU is being stored.
as for this case, i can only see, that topicstarter was being a victim of the static voltage in chain between PSU,human body and laptop

I'm always happy with your info

You know you could write up a guide, with all your knowledge (wait have you got one already? I better check)