Now you're playing with power 

Nintendo marketing slogan from the 1980s and 1990s.

No, Bobby, just because the Nintendo commercial said "Now you're playing with power!" doesn't mean you get to plug this pair of scissors into an electrical outlet!

Now you're playing with power by ekolis September 23, 2013

now you're cooking with gas 

Generally referring to someone going from average mental output to a better, more genius level of thought.

Person A: "I think I'm gonna stop doing all this complicated math by hand and start using a calculator."

Person B: "Now you're cooking with gas!"

now you're cooking with gas by Stormcastle October 15, 2010

Now you know 

Also known as nyk. The full phrase is 'Now you know better than that'. When someone says or does something so ridiculous, stupid, hilarious, or outrageous, the proper response to the situation is simple: "Now you know." nyk can be used in the place of lol for when you just don't know how to respond.

Dumb Bitch: I dropped $5 at Starbucks and $8 at Panera. The perfect breakfast!
Intelligent Person: Now you know.

Future Dropout: I totally bombed that test.
Friend: Well did you study for it.
Future Dropout: No.
Friend: Now you know.

Now you know by mintjellyfish November 12, 2011

Now you're on the trolley 

Expression used when someone FINALLY gets the gist of what you're telling/teaching them to do. Usually said for laughs or weirdness/British points.

Idiot: So you put the acid in and THEN the cheese?

You: No, BACON, then cheese

Idiot: oh THAT'S how you make a cheeseburger!

You: Now you're on the trolley!

Now you're on the trolley by skymar February 22, 2010

now you've gone and spanked the monkey 

Gone too far, cross over the line, exceed moral norms.

After deliberately eating the last Ho Ho when Bill's roomate, Chuck, expressly forbade him to, Chuck responded, " Now you've gone and spanked the monkey".

now you've gone and spanked the monkey by Guiseppemoondog123 December 10, 2009

Now you know 

What you say after you have informed someone with information they did not know

"Wow I never learned that men have the same thing that's inside of a vagina is inside of our assholes in my health class." "Now you know". " why didn't they teach us that? This whole time I could been using my vagina that's in my ass".

Now you know by Thm4754574 May 14, 2016

Now you know 

You use it when your friend is expressing skepticism towards some fact you've just told them, to hint that it's common knowledge and your friend is making a fool of himself by insisting to doubt it.

- "WTF" is an interjection.
- Really? I never heard of it.
- Now you know.

Now you know by Eikinkloster May 26, 2011