Title text: That card holds a refrigerator carton's worth of floppy discs, and a soda can full of those cards could hold the entire iTunes store's music library. Mmmm.
MicroSD is one format of the Secure Digital memory card format, used in digital cameras, cell phones, and other devices. It is very small, only 15×11×1 mm, but can hold as much as 128GB of data (as of January 2014).
The main character in the comic (on the right) thinks about all the ideas that could be expressed by the data in the microSD card, or in a library. He feels not just reverent and intimidated, but sexually aroused by the thought. As he begins to touch it, his friend is disgusted by what might happen if he uses the card as some kind of sex toy, and does not want to be involved if the card is lost afterwards (or ends up in some bodily cavity (or both)).
Randalls claims in the title text do check out. A high density floppy disk with a FAT format holds about 1.4 MB of data, and has dimensions of 90×94×3mm, for a volume of about 25000mm³. A refrigerator carton is the large cardboard box that fridges are delivered in. A typical refrigerator carton may be 1800×700×700mm, a volume of about 900000000mm³. So a fridge carton could hold about 35000 90mm floppies, or roughly 50GB. This is comparable to the storage on a single microSD card. A soda can (500mL = 500000mm³) could hold 3000 microSD cards, or store 50TB of data. However, the iTunes store claims to hold 26 million songs (as of Summer 2014), and allowing for about 2MB per song gives 50 TB of music. The claim that a soda can could hold the iTunes library seems to be reasonable.
Related to this topic is this xkcd What If blog entry.
- [Cueball and a friend approach a table.]
- Cueball: Hey, what's up?
- Friend: Shhhhh.
- Cueball: Hrm?
- Friend: There's a microSD card on your table.
- [A microSD card sits next to an assortment of coins for size reference.]
- Cueball (out of panel): So?
- Friend (out of panel): I dunno, high storage densities freak me out. A whole aisle of library shelves on something smaller than a dime.
- [The two people stand near the table, the friend peering at the coins and card on the table.]
- Friend: Libraries are unnerving enough-millions of ideas surrounding you, towering over you. These cards fill me with that same reverence, that same intimidation.
- [Cueball stands alone.]
- Friend (out of panel): ...that same faint arousal. Maybe I'll just touch it.
- Cueball: If you lose that card I'm NOT helping you find it.