Cellphones (ketai) are now regularly used by people all around the world. But in Japan, they've become a cultural item. Lots of stuff about cellphones just has to do with decoration. People hook charms on to their cellphones, and there are innumerable different kinds. The one on my cellphone is a hanafuda card with a bell. Other people have more sparkly charms, or ones that make noise, or several on one phone! The phone design itself is pop culture as well. One thing I noticed is that cellphones have decorative light patterns that serve little to no purpose other than to be cool, and let you know with some extra pizzaz that a text message just arrived. Simpler models just blink a light, much like most American cellphones. However, most of the fancier ones do more than that. My host mother's phone blinks a snowflake pattern, one of the ALTs has one that flashes several colors like crazy, and I've seen many more.
In Japan, manga is everywhere. Comic culture in the US is normally more of a cult or younger kids thing. However, in Japan, most everybody reads it. You can see kids reading it at home, businessmen reading it on the train, and it is everywhere in stores. There are all different genres to appeal to the various types of people, as opposed to US comics, which are mostly targeted at a particular audience. While I don't read it often, due to my lack of kanji skill, most Japanese people that I know from Earlham as well as people I've met during SICE have read at least one manga series.