Small "package" on console after starting X

["Patrick Wiseman" <pwiseman@gmail.com>]

Hello:

I have this odd phenomenon, which I suspect indicates some sort of attack.

After I start X, when I return to a console (with Ctl-Alt-Fx) there's
what looks like a little package sitting in the bottom, right-hand
quarter of my screen.  After I Alt-7 back to X, and then Ctl-Alt-Fx
back to a console, it's gone.  Any ideas what it might be, and how to
rid myself of it?  I've used rkhunter and chkrootkit, neither of which
reports anything amiss, but that may be meaningless.

Patrick