Spiders bots and other crawling things

In my line of work I get access to alot of websites, mostly those of midsized and large corporations. Now...on a website I was on earlier today I saw something interesting, they had a content management system (cms) wich listed the amount of traffic from bots and when they last visited, ie you could see googlebots last visit etc, now...this kind of got me thinking 'cause it ain't often that I come across stuf that makes me go "how the fook did they do that?" but now..I must admit that very thought crossed my mind. So...my question is:

How can you keep track of bots that visit your site and is it possible o make dummy pages so to speak so that malbots and spambots stay the fook away? I know, I know I can add image checks or math questions or something like that to the login, but to spare the users of that, is there a way to check if the visitor is a human or not and then redirect it if it isn't?

I thought about checking the visitors web browser, but maybe the bots use those too? Any thoughts?

The information needed to determine if a request is a bot or not is stored in the IIS Website logs. So doing a real time check like that seems unlikely. You would have to make a trip to the log and analyze the data to determine which page to serve up.

Is this question related to asp?