This video, or anime if you prefer, was inspired by the manga series called "Moyasimon: Tales of Agriculture." Manga is a Japanese word for comics, the literal translation is "whimsical pictures." This manga follows the life of a first-year college student named Tadayasu Sawaki who has the special power to see and communicate with microbes.
From what I have read at http://moyashimon.bleachwiki.net and on wikipedia at http://en.wikipedia.org/wiki/Moyashimon, the mini episodes of Microbe Theater, the first of which is embedded in this post, come as special content from the DVD of the anime adaptation of the comic.
While I have extremely limited knowledge of this art form, I find the characterization of the microbes themselves downright cute. Over the course of this week and next I plan to post more episodes with English subtitles.