CF is a tag based programming language for the web. It has been ported to Sun, RedHat and Win2k IIS
Unlike asp php etc there are a lot of applicaiton server type calls to handle sessions opening data cursors etc...
It is designed to be easy to learn and yet still be powerful. It has gotten a bad rap as many people have used it to create some very insecure apps. So in that sense it's like giving a 16 year old the keys to your sports car, sure they can drive it but chances are some one's gonna' get hurt.
Used properly you can do some pretty cool stuff very quickly and with very maintainable code.
It can be a server hog but that's true with most windows web languages.
Check out
www.fusebox.org