December 21, 2009: I've created a script that will create the animation in just a couple of clicks! You can view/download it here: [link]
Here's a nifty little tutorial for creating animated snowfall using GIMP GAP (GIMP Animation Package), which is a separate download from GIMP. The tutorial is written for people with an intermediate level of GAP usage, but I include a lot of screenshots and narrative to help out those who are still a bit new to the process. I certainly don't mind helping out you newbies, but please keep in mind that this is really intended for intermediate GIMP users.
The stock for the tutorial was obtained here: [link]
I received approval from the stock image creator to host this tutorial with his stock outside of GIMP (I've used a significantly scaled down version in the tutorial). However, downloading this tutorial does not give you rights to use the stock image for other purposes. You are only to use this stock for learning purposes. It's your responsibility to obtain approval from the creator before using elsewhere.
This tutorial is in html format. Download the zip file to a convenient location and extract all the files/folders to a convenient folder on your hard drive (ie..desktop) and then double-click the html file and you should be able to view it in your favorite browser from the comfort of your own home.
Let me know if you see any problems that need correcting. I look forward to hearing from you and seeing your outcome.
Until then, Happy GIMP-ing!