I picked up this sparkling cucumber water a few months ago and really love it. There's something so calming about cucumber, and this stuff is like a spa in a can. (Bonus: It's organic and has no sugar added.) It is lovely mixed with gin, but equally soothing straight from the can when you're having an emotional breakdown over a lost cardigan (not that I've ever been there...)
I had an airplane bottle of Tanqueray on hand, so I used that, but I think Hendricks (which is infused with rose and cucumber) would have been a perfect match.
A few thin slices of cucumber served as the perfect garnish, and provided a tasty snack once I reached the bottom of my glass. It was refreshing and soothing, perfect after a day running around or soaking up the sun. Probably not your best bet if you prefer fruity or overly sweet cocktails, but it suited me just fine.
[throw in a People Style Watch magazine and Essie's "Tour de Finance" and you've got yourself a back-porch spa. Or at least an hour of pure relaxation.]