Since I finally lost track about all my movies and series, I found a small nice website called trakt.tv. For anyone who knows anidb or MAL, it's basically the same for movies and series. For everyone else: You can manage the movies and series you own and / or watch and keep track on if you have seen them or not. On top of that, there's a neat calendar, which lets you easily follow the upcoming episodes of the series your watching. Also there's a wish list feature, which I use to add whatever movie trailer I see which wants me to keep that movie "on the radar". There's also a plugin for XBMC and some players (I think) to "scrobble" your files, meaning, that if you watch something, it will get marked watched on the website. It also has a recommendation area.

What I also like about this page: the VIP membership is pretty cheap, and the features are really nice but not necessary, exactly like premium should be. What the best thing about premium us: you get to vote on what the next feature is, which should be developed by the admins. So you can directly influence the website. I think that's really cool. Also, I'm not affiliated with this website, I just like it that much :P