I'm a science teacher at an Australian public high school. I have begun packaging up the software that I've created over the last few years of teaching. Created organically and out of necessity, they are used by teachers within my school and I'm hoping that you will find them useful too. My goal is to see these tools in the hands of as many educators as possible.
So far I've polished off a seating plan generator called Termites. You input the relationships between students and it automatically places them into seats in your room layout. The tricky part is that it keeps students with good relationships together and students with bad relationships apart. I'm sure you don't need to be told how complicated the web of relationships in a classroom can be ;)
Of course, you can do all the other essential things too, like force a particular student to sit in a particular seat, or even float individual students to the front or back of the room. It then considers the web of relationships and places everyone else around them.
So basically, Termites creates seating charts just like you do, only it does it a lot quicker and more dynamically. It's a simple little tool but everyone using it finds it invaluable.
It's available for download at termitesapp.com
There will be a bunch more software coming as products and web apps. I just need to find some time away from the classroom to package it all up!
Anyway, I would love some feedback.