They blocked executables on floppies, but if you copied something to a floppy as a .txt file to My Documents and renamed it, it was runnable.
They then blocked executables in My Documents, but if you put in a batch file, that'd still run.
They then blocked batch files, but if you created a shortcut to "cmd.exe" and ran that off a floppy, you got a shell prompt, from which you could run whatever you want.
They then blocked executing "cmd.exe", but the initial response didn't also include "command.com"...
_Unfortunately_, at that time, I'd already discussed the "cmd.exe" loophole with them, and the "command.com" loophole was basically the same thing that I'd already been told not to do... so I got detention for this one, and promptly stopped.
In another school (where IT was much more advanced, likely a lot like you've encountered), I put a file called DukeNukem.exe on the school-wide network share, and it didn't take long for people to discover it. It just showed an error, game needs some extra permission, and asked you to enter the password to try again. Well, people did that of course and the game didn't work. But another file on the network drive collected EVERYONE's password, one after the other, it took a few weeks until they caught me. They were able to use some Novell admin ninja something something to figure out who placed the file there and again, I was kicked out of IT classes, no other harm.
When the IT guy talked to me, he even said he'd seen Rainmeter in a magazine and tried it out at home and thought it was pretty cool. But the admins had watched Hackers too many times, it seems, and thought it appropriate to treat me like a delinquent :P
Edit: Looks like Rainmeter is still alive and kicking! Maybe I'll give it a revisit