Off Book is a new online series from PBS Arts. In their fourth episode, shown below, various web people explain online visual culture -- web videos, animated GIFs, and (ugh) "memes." It's worth a look, at the very least for the origin story of Nyan Cat. For previous episodes check out: Light Painting, Typography, and some video that YouTube is reprocessing right now (perhaps it'll finish by the time you click on it).
Stick around until after the credits. The smartest comments in this thing are just after the eight-minute mark -- this meme stuff is not about making money, it's about making your thing; the "meme" or viral nature of online visual culture is an effect, not a property of the artistic process.
(Via Laughing Squid.)