if that's the GIF I'm thinking of, it's saved as an indexed-color greyscale GIF, which is pretty tiny. If they saved it as a 2-tone (Black Or White) GIF, then each pixel requires a Bit of memory... not even a Byte. Also, they usually record a value of how many pixels in a row share the color, and only save the pixels that change color per frame, instead of the color value for each one, frame by frame.
Long story short, the Gif, even though animated, probably takes up a fraction of the memory that most single frame photo JPGs do, and each user only has to DL the image once.
I went to get my new car repaired (*grumble grumble*) at the dealership today, and while there ran into an old highschool aquaintance of mine. We had slight drama back in the day, since his girlfriend was one of my best friends, and used to hit on me rather frequently... and it was a bit awkward. Sad part was in the conversation itself though:
S: "Hey John? It's me, Solifuge!"
J: "I know."
S: "So, what's up?"
J: "Not a lot. Where you working at these days?"
S: "Oh, I'm... doing environmental work at a manufacturing company. It's an internship-sort-of-thing, but I'm not really planning on staying there for long."
J: "Alight."
S: "I'm still taking classes at University too, so yeah... how about you?"
J: "I'm working on Green Energy projects for a big Tech Company."
S: "Oh yeah? What kind of stuff?"
J: "Well, it's pretty confidential, but one of the things is a hydrogen fuel cell car that uses solar energy. It's pretty cool, getting a bunch of cutting-edge technology to play with and all that."
S: "That does sound pretty neat."
J: "Well, the technician's here. Gotta go."
S: "Good seeing you John."
He apparently got married not long back, judging by the rings, and is off working in a pretty cool field with his degree... while I'm still only a little more than halfway to graduation, and working a job I don't like, and which I'm basically just getting a paycheck out of.
Blah... its reasons like this that I never use Facebook. Just makes you feel bad for all the things you haven't done, and pushes you to compare yourself to your peers.