When I booted, slack went through the occasional hard-disk check for errors, and found some. After correcting them, my kernel kinda went haywire. I had trouble with installing video drivers, and I got all these messages about errors loading hotplug.

My video drivers work now, but I still get the hotplug error like ten times per boot.

/etc/hotplug.d/default/default.hotplug: line 1: error: cannot execute binary file
. . . no modules for PCI slot.

I also get an occasional

. . . no modules for USB product 0/0/0

and one is

. . . no modules for USB product 413c/2001/1

I'm running kernel 2.6.4, in 2.6.2 I only get the "no modules" error.

I checked for /usr/bin/env and it wasn't there. So I copied it over from the bootable slack disk, thinking it would be able to run env. I made sure it is executable and part of the group bin. Still doesn't work:

root@computer:~$ env
-bash: /usr/bin/env: cannot execute binary file


I also noticed that the 'clear' command stopped working. It turns out that clear was still there, but clear is just a shell scrip that runs 'tput clear'. Tput was gone, so I replaced that too. Clear still doesn't work either:

root@computer:~$ clear
/usr/bin/clear: line 2: /usr/bin/tput: cannot execute binary file

Any ideas?

you should reinstall, or install binutils.

although. env is a builtin bash command.

your installation is funky, obviously.

Installation worked great for a few months. I think my fixed errors borked it. What's binutils?

I would suggest using whatever means you have to verify your other installed packages, logs and auth are verified clean before reinstalling stuff.
Just in case, I'm not hinting at a compromised box.