For what its worth, I have had Recovered files in my Trash since installing Tiger on my iBook. I did a clean install.
The "recovered" files are random, depending on what I have been doing before I reboot. They always show up after a reboot.
I just installed the iTunes 4.8 update, rebooted a bit later, and now I have the following:
com.Apple.SoftwareUpdate.HVnAAl
> SoftwareUpdateCheck.pid
(the top item is a folder containing the bottom "pid" file.)
It's annoying, but more than anything I'd just like to understand why this is happening.