Easybib just released an iPhone app that allows you to scan a book's ISBN code, then it creates a works cited entry for it in APA, MLA, and Chicago. You can then email the citation to yourself. Pretty rocking for students and academics. It's free.
I think there's something similar for android.
In this world of sin and sorrow there is always something to be thankful for; as for me, I rejoice that I am not a Republican.
- H. L. Mencken