It has come full circle for Idolm@ster fans with regards to the anime adaptations. Cruchyroll with the legit series that feature the music from the games, The Anime Network showing Xenoglossia that has the idols hanging out with mechs, and, out of nowhere much like the mechs, Funimation has started streaming Puchim@s on their main site and on YouTube.
So... what the hell is a Puchim@s? They're basically babies (think Muppet Babies) of the 765Pro idols we know and love, along with their exaggerated traits. Afuu eats onigiri and sleeps slightly more than Miki, Yukipo digs holes -literally- and bursts out in moe goodness like Yuhiko, and Chihyaa bites anyone with ぼいん ぼいん. The only oddity is Haruka's puchidol counterpart, Haruka-san, who multiplies when she comes in contact with water much like a Mogwai.
The anime is based off a 4-koma manga, and the episodes last about as long as reading a couple pages, lasting about a minute outside the ending theme.
As to why these things exist... I don't know. Namco being Namco, I suppose. Funny enough, though, I believe this MAD predicted the arrival of the massive Haruka-san:
matty note: There was also the OVA of Im@s that was released with Live For You on the Xbox 360 and the three episodes released exclusively on the Shiny Festa PSP games.