If it has tits or tires, it's going to give you problems.
Great site Ghost. Perfect for me since I am studying for the N+ right now and the two areas I am weak in are subnetting and OSI model. I doesn't help that it is summer (hard to study when it is nice out). Anyway, I think this site will give me some practical training that will let me understand the concepts.
Nice link but where do you start if you want to subnet an existing network that is already a mess?