Anti-Plagiarism Companies
 

Other than the hyperbolic claims, Gotcha!'s site does not offer much information on the how of their plagiarism detection methods.  At any rate, they do offer a very generous one month trial use.  After 30 days, Gotcha! charges only $9.95 per month, a paltry sum compared to other detection companies.

Glatt Plagiarism Services
Glatt provides three different programs: tutorial, screening for faculty use, and self-detection for student use - at several hundred dollars per program.

Essay Verification Engine (EVE)
EVE scans student papers and tries to find an online match for any student text. “If it finds evidence of plagiarism, the URL is recorded. Once the search has completed, the teacher is given a full report on each paper that contained plagiarism, including the percent of the essay plagiarized, and an annotated copy of the paper showing all plagiarism highlighted in red.” Company offers free 15 days trial service.

Turnitin.org
The detection system of choice for university's like Cornell and Rutgers, Turnitin offers students research resources and opportunities for peer review in addition to the plagiarism detection package.  To assess student work, Turnitin interfaces with the top 20 search engines as well as its own data base reserve of papers.  Take the Turnitin power point tour, or go for the one month free trial.

WordCheck Systems
"WordCHECK/RA is a 'proprietary repository' - a protected database of digital documents, available only to the individual user of the software."  Free demo is available.

Copycatch
Software is available for stand alone or networked machines.  This British-based company claims 100% accuracy in identifying borrowed material.

Plagiserve.Com
Plagiserve checks student papers against online paper mills, popular digital encyclopedias, and its own data base.  Service will uncover undocumented passages as well as texts pilfered in their entirety - promises 12 hour turn around.

Articles

Can Tech Detect College Cheaters?
ZD Net: Technology News Now
Assesses effectiveness of plagiarism detection software.

Plagiarism-Detection Tool Creates Legal Quandary
Andrea L. Foster
The Chronicle of Higher Education
May 17, 2002
Author reports that "some college lawyers and professors are warning that one of the most widely used plagiarism-detection services may be trampling on students' copyrights and privacy."

Anti-Plagiarism Experts Raise Questions About Services With Links to Sites Selling Papers
Jeffrey R. Young
The Chronicle of Higher Education
March 12, 2002
"Two online services that help professors check student papers for plagiarism -- PlagiServe.com and EduTie.com -- appear to have ties to Web sites that sell term papers to students. That has some professors worried that the two services might be secretly selling the very papers that they claim to check."