I have a Debian 6.0.1 vanilla install, and I use PUTTY to ssh into it. I will usually have 3 or 4 PUTTY login shells running at the same time.
What I'll find is that if I leave my computer for a couple of hours, I'll find that 1 out of 4 shells will be terminated. If it were a network issue, I would expect all 4 sessions to be down, but it's always just 1 or sometimes 2. It's really strange.
Would anyone know what this phenomenon is? Is there something in the logs I could use to figure out what is going on?