To the young (or young at heart) ADULT ladies. . . please help me out!?

i need advice on the "perfect" date. i'm doing something this weekend with a girl that has been a friend for a few months, and we have gone out a couple of times as more than friends, but haven't done much more than kiss. we've done the dinner and a movie thing but i would like more time with her to talk and such. the thing is, i'm leaving for a few months (she knows this) and would like to do something romantic but also a lil outta the ordinary. she is VERY special to me, so i am not just trying to get her in bed, but do want to do something she will remember. ALL advice is appreciated. btw - it is cold outside, so it'll hafta be something (at least for the most part) indoors. thanks again to all who help. already asked this once and got a few beautiful ideas - thanks to those who helped other than mary w
p.s. we could've slept together (were going to get a hotel after halloween) but she was drinking, and i don't need to take advantage of a drunk girl.