Bryan's solution using the vid extension is good---except that this
extension does not work for many of us using Windows: it creates a video
file that does not play properly. (This was discussed somewhere in the
release notes, as I recall, as a problem not likely to be fixed soon.)
A reliable alternative (also mentioned on NetLogo's Stackoverflow site)
is to export the interface (or view) every tick and then use separate
software to turn the exported .png files into a movie.
Modifying Bryan's code, you can use this:
repeat 100 [
export-interface (word "Frame" (10000 + ticks) ".png")
This will produce 100 files labeled Frame10001.png to Frame10100.png.
The software I use to assemble these .png files into a movie is GIF
Construction Set Professional--$30 at
http://www.mindworkshop.com/gifcon.html. You can figure it out in 5
minutes and make a movie in 3 minutes. You can control the movie's frame
rate, compress it to reduce file size, and save it as .gif, .avi, and
several other formats. Movies with 100s of frames do get cumbersome.