If you hate how diluted cocktails get as the ice starts to melt, this tip from the folks at The Kitchn can keep your tasty drinks flavourful and delicious even as the ice melts: make your ice out of tonic water instead of tap water. If your cocktail already calls for tonic water, you'll get that flavour as the ice melts, and even if it doesn't, the taste may be better than essentially adding water.
Granted, this trick works best for cocktails that already call for tonic water, and by freezing the tonic you're not getting the carbonation that you might enjoy if you use it as a mixer. With that out of the way though, all you have to do is pour tonic water into ice cube trays and pop them in the freezer until they set. The next time you make a drink, toss in your tonic cubes instead of regular ice.
Some of the commenters there suggest metal ice trays over plastic ones, if you're a believer that better ice makes better cocktails, and others suggest using Whiskey Stones to chill drinks without diluting them, a topic we've covered before. Do you do this or have another method of keeping your drinks chilled without diluting them? Share them in the comments below.