One of my closest sisters was proposed to at our Fraternity Formal. May be common place to some, but to us it was a definite first! Every year, we have an award for "Girl most likely to marry a fraternity man" and she's won it for the past three b/c she's had a promise ring. Last year her future husband got up to announce the last award, and we all started to smile b/c we knew she was going to win again. He said a little intro, proceded to say that this year, he wanted to go one better and instead of "Girl most likely" make it "Girl most definitely". Then he got down on his knee and...
Lemme tell you how funny the pictures are from that night, of us stunned in the crown, then all tears and laughter...
Now, I guess this would be difficult if your friend's not a fraternity woman, or if they don't have such an award. Nonetheless, I love telling this story!
I also like the toolbox idea! My dad once gave my mom a ring hidden inside a box of new windshield wipers. She was sort of let down by the unromantic-yet-sweet in an "I'm thinking of your safety" kind of way 'till she opened up the box and out fell the jewellery box. You can use a ring as an ornament on a Christmas Tree, or put it on the top of a tree as a star. If they have pets, he can tie it to a pet collar... y'know, looking at these ideas, they definitely lean towards the nonchalant surprise tactic, which I have to agree with aephi alum is the way to go unless he wants to spend big bucks on a destination proposal!!