A growing number of professors use Turnitin.com to catch students submitting plagiarized papers.
Now the professors themselves are being scrutinized for plagiarism when submitting papers to scientific journals:
From "Science": Déjà vu, an online database that bills itself as "a study of scientific publication ethics," has prompted discussions with journal editors and at least 48 retractions of suspicious papers. Some journals now run accepted papers through eTBLAST, the freely available software behind the database, to hunt for duplications prior to publication.
links:
http://www.sciencemag.org/cgi/content/short/324/5930/1004
http://invention.swmed.edu/etblast/etblast.shtml