Some bacteria are beneficial. Are there any beneficial viruses?

http://www.madsci.org/posts/archives/200...





http://www.bio.net/bionet/mm/virology/19...

Some bacteria are beneficial. Are there any beneficial viruses?
Yes


and such viruses are called bacteriophages (commonly)


they can eat harmful bacterias.
Reply:Yes, definitely! In biological reasearch we often use viruses because they can be beneficial and duplicate very quikly! :)
Reply:Yes. The tobacco mosaic virus. It decreases the growth rate of a plant that's known for its addictive qualities and the propensity of its abuser addicts to litter.