I spent the better part of the evening trying to find a plagiarism checker that would allow me to upload multiple files, run a thorough scan, and produce a printable report. Almost all of them are simply text boxes that you paste part of a paper in and then it runs it through Google (as if you couldn't just copy and paste it in yourself). I only have one large written paper project each year (I might do two next year, but even one is such a headache), but last year I had a plagiarizer, and I found one this year too even after I stressed that they would receive a zero if I found plagiarism and that I had a plagiarism detector that would let me find any hints of it (I didn't at the time but I do now!). In any case, I had thought I could find a good free one, but alas, that's not the case. And many are really expensive. I was hoping to be able to just throw them all into a scanner and see all of them at a glance, but they charge by the word. It's alright though, because I can tell usually at a glance if a paper is copied and pasted from Wikipedia or not. I purchased the plagiarism detector mostly for its report generating abilities, which I need to back me up in the case of overly defensive parents and students. PlagScan seems to be reasonably priced for individuals who are just scanning a paper here and there to double check or to generate proof, because there's no way our school would buy a school license. The reports it gives are very thorough, professional looking, and impossible to argue against. What do you guys use?