How about comparing to the lifetime of one person? With the US average life expectancy (78 years) that means you'd have to upload 800 objects/second for your whole life to get to 2 trillon :)
Edit: One S3 object for each fish in the ocean (3 to 4 trillion) could also be a nice future milestone (if also slightly underwhelming :)
Edit2: I also love the eye blink as a unit of time. Each time you blink (average is around 15 times a minute), XXX more objects will have been uploaded to/requested on S3
My math is probably wrong... but I believe if you ate a twinkie for every request at the end of a year it would take 1,350 Blue Marlin heavy lift ships to move you across the ocean.
Oh, oh, I like doing these analogies, and we badly need AWS stickers for the office.
A typical grain of beach sand – which must be about the lightest solid thing that’s easy for most people to envision – is 3 mg. That many grains of sand would mass 6e6 kg (6000 metric tons), which in turn is near the upper limit of masses that make sense to most people in everyday terms.
So you could say that if every S3 object were a grain of sand, S3 would be 3× the launch mass of the Space Shuttle, or somewhat more than the gold held in Fort Knox, or as much as the heaviest living thing: http://en.wikipedia.org/wiki/Pando_(tree)
And the the 1.1 million requests per second would be about 3.3 kg, or as much as a gallon of milk/water.
Imagine each object being a person, and imagine a room large enough to fit 10 000 people, the size of a small village, standing side by side, barely being able able to touch each other's hands, spanning roughly 15-20 km.
Now imagine putting 9 999 people behind every person.
And finally, imagine stacking 9 999 on each of these million people's head. That's twice the height a normal airplane flies at.
Then double that number. That's how many objects have been created so far.
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A bit long, but I think the roughly human scale numbers, 999s and even more effect makes it almost imaginable.
EDIT: Another one - you could fill the whole of manhattan with cents and still have money to spare.
(Manhattan is 87.46 km^2 and a coin is less than about 40mm^2)
It's so many objects that you had all their names printed out, and spent the rest of your life reading them, you wouldn't have time to get to the end.
In fact, even if you and all your friends spent your lives reading the lists of object names, you wouldn't have time to get to the end.
In fact, even if you and all your friends and all of their friends devoted your lives to reading lists of S3 object names, you wouldn't even make a dent because new objects are arriving faster than you could collectively read their names.
If each object is a megabyte, you could stick them on microSD cards packed in a cube as tall as an adult.
(1 card is 0.11cm x 0.15cm x 0.01cm, 32GB. 32k objects, 31.2M cards needed. 165 cm x 165 cm x 165cm = 110 * 150 * 1650 cards = 27.2M. Instead of 165cm which is 5 and a half feet, say 6 feet, so try 166 * 122 * 1829 = 37.04M, enough to use some error-correcting codes just in case.)
I like to use dice to think about storage. If a byte is the size of a die (let's say 1cm^3), then a kilobyte is a 10x10x10 cm^3 cube. A megabyte is a 1m^3 crate, a gigabyte is a 10m^3 house, a terabyte is a 100m^3 tall building, a petabyte is a 1km wide borg cube etc.
If each object was written on a single standard 8 1/2 x 11 inch piece of paper and stacked up, the stack would be about 125,000 miles high (about half the distance to the moon).