Question: I want to set up an automatic task that will automatically delete files older than X days from a specific folder. I'd prefer to do it without having to install any 3rd party software, but I'll be ok if it's a very small and simple utility. 

I want this to force me to keep my files organized. I am setting my browser to download to a standard folder, and then with this script to automatically delete files older than a week, I will be forced to move & organize downloaded files I want to keep.

Answer: 
How about [Belvedere](http://lifehacker.com/5510961/how-to-automatically-clean-and-organize-your-desktop-downloads-and-other-folders) from one of [Lifehacker](http://lifehacker.com/)'s editors. 

![alt text](https://i.stack.imgur.com/1ed65.png)
There's a windows command called forfiles. I think it was on the windows 2000 resource kit.
I found a link to it from petri's web site: <http://www.petri.co.il/download_free_reskit_tools.htm>
It has a lot you can do with it including removing individual files based on how old they are or whole directories.