Movie Search Engines:
These are just search engines that do basically what google does but filters out the search so you can find movies that are streamed on the internet from other websites.
http://www.movinex.com/ (Yes this is in spanish! You can still search for English movies)
Definite Legal Websites:
Websites that stream legal movies paid for by advertisements.
Websites that stream movies from other sites and are considered to be legal:
*Caution: There is some debate as to whether this site is legal. Their disclaimer is (Disclaimer : WatchMovies.net is absolutely LEGAL. It only contains links to other sites on the internet \. (Rapidshare, 56.com, toudou.com, Veoh.com, etc) We do not host or upload any video, films, or media files. (avi, divx, etc ) WatchMovies.net is not responsible for the accuracy, compliance, copyright, legality, decency, or any other aspect of the content of the linked sites. If you have any legal issues please contact appropriate media file owners / hosters.)
This site contains a lot of fun tasteful short films.