Many white wines work better chilled, so if you pull a bottle from your wine rack, it will take a while to lower the temperature in the fridge. It's much quicker to cool down individual glasses of wine, and a stash of frozen grapes is the only tool you need.
All you have to do is toss a few frozen grapes in your glass before you start drinking. Unsurprisingly, red grapes are perfect for red wines, and white grapes go well with white wine, but they won't pass much flavour through the skin, so it's not a huge deal if you only have one variety.
The advantage of the grapes is that they won't water down your drink as ice cubes can. The grapes might affect the flavour of the wine ever so slightly, so I probably wouldn't use this with an expensive vintage, but it's perfect for cheap table wine. Plus, once you're done drinking, you have a delicious snack waiting for you at the bottom of the glass.