In a continuing theme of web-based manga and gag manga being developed into web-based anime, the latest such entry
is one of Japan's most popular online comics, Kuruneko-Yamato's (I'm betting that's a pen name) comedy Kuruneko. The web shorts will air on Nico Nico Douga, of course, and revolve around an old cat lady. Except she's not really very old, and she drinks a lot of sake.
The webmanga is very popular, and Enterbrain-- who publish the tankoubon –actually calls it the most popular. They may have based that on sales of printed tankoubon; 350,000 of all three volumes (combined) have sold in Japan to date, according to Enterbrain's site.