I was looking for episodes on the internet of some TV shows for my sister and was having a hard time finding "So You Think You Can Dance" (which apparently Fox does not put on their website). But I looked for anything on YouTube and found Snape teaches Slytherins to dance. It is excellent and was created using the game Sims 2.
And fourth-rose has also written a story that goes with the video, in which Professor Snape, in order to make sure Slytherin doesn't make fools of themselves at the upcoming Yule Ball, teaches them to dance. It is absolutely hilarious and well worth the read.
Looking around, I found that people were writing additional Harry Potter stories using Sims to illustrate them. Here is a page of Sims outtakes from a chapter of one of those stories by CloudlessNights. You can find her work by checking out her tags and links, like Harry Potter starring The Sims: Book 1 - The Philosophers Stone and Book 2 - Chamber of Secrets.
She also has a great series called the Timeturner Incident written by the Sims. As she says in episode 1: "Please bear in mind that visiting sims can't be controlled, so whatever they did, they did it all on their own accord. I was only watching in shock, awe and amusement, and taking a lot of pictures ;-)"
And check out the Harry Potter Sim Videos on YouTube. The assortment of creative ideas is outstanding. And there is an outstanding series of Harry Potter and the Order of the Phoenix with voice actors and everything. Here is chapter 1 (he has disabled embedding the video). These were created starting in October of 2005. It is interesting to compare to the movie.
And of course, if you just search on Sims, you end up with a ton of fun videos. Who would have thought people could be so creative with this new medium?