If you like your drink cold, try these stones.
Whisky Stones
I've seen these before but have always been a little wary of what they might do to the inside of a nice scotch glass. Also, I wonder if they're completely inert or might they possibly impart a flavor of their own (or if porous, previous pours)? Has anybody used them? I might be interested in buying a set if I knew a little more about them.
FWIW, I generally add a touch of water to my Scotch (Bourbon, for me, is almost always on the rocks).