Help! We need a birthday prank!

[BrerLizzie]

My friend turned 18 yesterday and we want to mess with her a little. She'll get a kick out of it. She likes weird things.
My friend Veronica and I decided we'd have some fun and surprize her. We had to do it tonight since it's the closest day to her birthday that we had the next day off of school.
I need some ideas on what to do. The only thing is that it needs to be cheap and sort of easy to clean up. We'll be going over to help her whenever she decides to do it so her mom won't totally hate us.
Anyone got any ideas?

 

[Daisy Duck 5]

Get a packet of instant milk and put it in someone's bed on a particulary hot night. In their sleep, they will sweat, and in the morning the milk will have mutated into SOUR STINKY MILK! They will stink for a week.

Freeze cans of shaving cream. Then carefully use a dremel tool to cut through the can. Put the frozen contents into someones room, and when it thaws out it will expand to full size, which is a hell of a lot of shaving cream.

Go to the dollar store and get a bunch of those cheap travel alarm clocks, set them to go off every half hour in the night, and then hide them throughout the room. Drives them nuts!

 

[Sthronds]

My college roommate and I dixie cupped a professor's (That we loved) office back in college which was difficult but fun. It involved placing little cups with a little bit of water all over the floor of his office. The only bad thing was we used cheap cups and they leaked. Oops. If you used plastic cups, it would work well.

We also filled his office with balloons. I mean completely filled.

I don't think he ever found out it was us!

 

[pfishgirl]

You can buy one of those prank lottry tickets... It is a scratch off Birthday lottery ticket and I think it says you won $100,000 or something like that.. Just put it in her Birthday card with some real lottery tickets, she'll never notice it's a fake..

Can you fill her car with Balloons???
School locker ??

 

[pattyT]

I would go buy 18 pink flamingos (or other not so subtle lawn ornaments) and put them on her lawn

 

[BrerLizzie]

these are great. we've already filled her locker with balloons. we did that when she turned 14, but she loved it so we might do the car too if we can get her brother to unlock it.
i think we'll try as many of these as we can pull off. we had to postpone untill tomarow because veronica's mom wouldn't let her go out tonight since she's working tomarow morning. her sleep over party is tomarow so we'll have access to her whole house. she sleeps like a log!

 

[drayke]

turn all the furniture in her room upside down and put what ever was on top, on the new "top" surface.