If you are looking for a free solution to access Wikipedia information on your cellphone device, check out the Java-based tool
JOCA by German company InteracT!V GmbH, which uses GPRS to access updated information from Wikipedia. Besides Wikipedia, JOCA also offers other (however mostly German-related) media services, including a TV guide, radio playlists and traffic information.
Alternatively, you could also use
Wapipedia or
Wapedia, which both work with any mobile browser; then there is the WAP solution
Maxipedia; and finally you could download the entire 1GB+ Wikipedia database, put it on an SD card and
view it with TomeRaider. A beautiful Plucker version is also
rumored to exist, but Hacker hasn't decided to make it public yet
[via
press release]