[WalterGR]

I managed to crawl and store (in mongo) more than 300k movies from IMDB in just a few hours

Did you know that IMDB makes a subset of their data publicly available? http://www.imdb.com/interfaces/

[alexbardas]

Yes, but it's hard to tell how complete and updated that subset is. There is (was until few weeks ago apparently) also http://www.imdbapi.com/ which was retrieving their data by crawling. Unfortunately, it was shut down.