Inspired by this compilation at Slate (with some help from these lists from Entertainment Weekly) here’s my stab at the top 10 movies of the decade:
1. Eternal Sunshine of the Spotless Mind (2004). Seldom have I finished a movie feeling so satisfied, like I just finished a good meal.
2. Moulin Rouge! (2001). An odd choice, but I loved this movie so much when I saw it in the theater. It was so original, so layered in its storytelling. And it doesn’t hurt that it was my future wife’s favorite movie. Yes, Come What May was sung at our wedding, what’s it to you?
3. Casino Royale/Star Trek (2006/2009). Two reboots of legacy franchises with high expectations. Both exceeded expectations and surprised die-hards by taking new directions with established characters. Absolutely loved both movies.
4. The Blair Witch Project (1999). Ok, this is a cheat, but October ’99 is close enough to 2000 to count. Plus it has to be noted how important this movie was for not only how it was made, but how it was hyped. It was the first “viral” marketing campaign. Lost wouldn’t be the same without it. So/so movie, but played to great effect.
5. American Beauty (1999). My second cheat but also included because of the trend it started: the hyper-realistic story telling without any true protagonists. ‘Reality TV’ without the c-list celebrities. This is what you’d see if you put a camera on an average American family in 
suburbia, and it’s not pretty. I’ve never spent so much time in the parking lot afterwards taking about the movie I just saw as I did with this one.
6. The Passion of the Christ (2004). Demonstrated that christians (intentional little c) are a viable niche market. Good or bad thing?
7. Gangs of New York (2002). A movie that completely overwhelms you. Between the stellar acting, the portrayal of the grittiness of the time period, and the brutal violence of it all, this movie makes me very grateful I didn’t live then. It also ushered in the trend of the ‘histo-drama’, released during the Oscar push that includes movies like There Will Be Blood, which top many lists, but wouldn’t even have been made if not for GoNY.
8. 25th Hour (2002). New York post 9/11 plus Spike Lee. Add a little Ed Norton and you get one of my favorite movies.
9. Gladiator (2000). Never has a movie inspired so many sermons. But revolutionary in it’s combination of the special effects of a summer popcorn flick and the depth of a period drama. Yeah, it’s still just a popcorn flick. But a darn good one.
10. Amelie (2001). Cute. Quirky. Foreign. A movie I loved even though it doesn’t fit in any of my usual favorite molds.
Honorable mentions (maybe not top 10 worthy, but worth a watch if you haven’t seen them):
–Requiem for a Dream (2000). I had a tough time leaving this off. Soderbergh–ish cut-editing. Realistic portrayal of addiction. Don’t watch on a date (ahem, Jim).
–Once/Bella (2007/2006). Little indies that could. Great feel-good movies.
–Friday Night Lights (2004). I needed to include a sports movie. Not sure if this was the best of the decade, but it’s close. Also the first that came to mind.
–Narc (2002). In my opinion better than Mystic River, The Departed, We Own the Night and every other police drama that came out in the last decade.
–WALL-E (2008). This needs to be in the list above, but there’s no room. Hardly any dialogue, but incredibly deep satire for an animated kids’ movie.
–The Prestige/The Illusionist (2006/2006). In the tradition of Armageddon/Deep Impact and other duo/copy-cats, come these two period pieces about magicians couldn’t be more different. And unlike Armageddon/Deep Impact, both were good. Very good.
I’m sure there are others. So help me out what makes your top 10?