for me, not using a computer to control my grow room is like using a horse and carriage to go to the store. no other way makes sense to me. I've seen a few other people online with similar interests in computers. post some pictures, show us what you created. take a chance to brag. I started out using the serial port but moved on to usb for (hopefully) higher reliability. I'm putting together an open source commercial program for this, with support for different types of hardware interfaces. I'd love to see what more people have come up with on their own. when I release my program, I'll be looking for lots of input and comments.