My DD17's friends still talk about hers, too, but boy, it was done on the cheap compared to some of these descriptions!

The total cost for this one was about $350.
She had about 18 friends (boys and girls) over to our house/yard for her 16th. We have a gameroom with lots of pinball machines, so had contests with fun/silly prizes for the high scores, other corny/retro teen games I found online that the kids loved, an "endless present" game that we always do for our (younger) kids parties (wrap a prize - this one was a cool t-shirt) in LOTS of layers of newspaper, boxes, brown paper grocery bags, shipping tape, string, duct tape, rope - whatever you can find - and put candy in the layers. The kids sit in a circle and each one gets 10 seconds to unwrap as much as they can and anything that falls out while they unwrap they can keep. They keep going until someone gets to the prize in the center. This has now become a "classic" at our DD other friends' parties and now she always gets asked to bring one along as her present. (It is amazing what small and surprising things entertain kids...!

) You can do this for kids of any age - vary the gift inside and wrap the layers more snugly or not, depending upon the number and age of the participants.
My husband is a (hobby, but VERY good) magician, so there was a magic show, too. This was a huge hit. We did a Chinese food buffet and lots of juices and sodas, a homemade cake, and lit a bonfire/campfire in the pit in the backyard as darkness fell. I bought flashing light-up LED (not glow) necklaces from glowsource.com and they ALL (boys and girls) wore them, and one kid brought a guitar and they all sat outside singing/laughing/talking for hours. We sat inside (but came outside to

"check on the fire...") occasionally, but there was not a single problem. In all, the party lasted for about six hours. When the parents/siblings started to show up for pick up, the kids howled that they wanted to stay longer - so many did! They all got goody bags upon leaving - containing jumbo chocolate bars, Jones sodas, and goofy/cheap snacks like Pringles and Smartfood popcorn. They all were SO excited about the goody bags - they hadn't had any at parties in FOREVER, they said. They enjoyed the walk down "Memory Lane" too, I guess!
It was fun to type this all in and relive the memory - our daughter had a wonderful time with a great group of friends. We are so lucky that this is a good bunch of kids and that they still talk about the party as a truly fun one.