I was wondering if any of you hardware enthusiasts out there have taken to creating your own usb key loggers yet.  I'm pondering looking into it, and wondering if anyone has had any kits or such they've liked... or done much in the way of comparing them.  The price for a usb keylogger is coming down though... I found a few decent looking ones for 60ish for a gig of key strokes.  Any thoughts?

So far I have only built a PS/2 Keylogger by myself. While testing around it worked with most of my PS/2->USB adapters but unfortunately not with all.

Currently I am also writing an article about hardware keyloggers where I also compare different ones but it will published only in a few months unfortunately because of various reasons.

So far I can tell you that there are not major differences between most products available. However, I haven't testet them as extensively as I want yet.

I heard that soon a tutorial will be published on how to create a wireless hardware keylogger by yourself. Although I am not sure if it was USB or PS/2..

For others who would prefer to buy a hardware keylogger rather than build it by yourself I am currently working on some reviews about products available on the market.