It's clear. It's forgettable. It wasn't always that way. Consider ice.
When Starbucks rolled out its Trenta this week, a number of commenters correctly pointed out that the 31 oz. drink contained ice cubes. Although I haven't tried one myself (and haven't been able to reach Starbucks), the Trenta probably has closer to 20 fluid oz. of iced coffee or iced tea—and might not actually equal the volume of your stomach.
Either way, it reminded me of something Mark Twain said (which Ben Schott and Andrew Beahrs both resurrected recently): "Only one thing... can be called by the wide name 'American.' That is the national devotion to ice-water."
Twain said that in the 1890s, a time when ice was being pulled out of frozen rivers and ponds in Maine, Wisconsin, and Pennsylvania and shipped all across the country. Ice was like other foods with regional variations in flavor. Before the Civil War, when bartenders in New Orleans poured a mint julep, they poured it over ice pulled from ponds outside of Boston.
As Gavin Weightman writes in The Frozen-Water Trade, the ice trade started when Frederick Tudor, a 22-year Bostonian, decided to ship 80 tons of ice to Martinique(!). This paved the way for the definitive American beer (lager had previously only been brewed in the winter) and ultimately helped created the idea that refrigeration was a household necessity—for food and for comfort.
Now, ice and the energy used in making it is something that's pretty easy to forget about. Maybe it's time to reconsider.
Patent drawing via E. S. Field, 1880. Ice Cutting Machine. US Patent 234397.