Today our server was having problems letting people on, so in his infinite wisdom the sysadmin had the server rebooted, of course Oracle, Applications, and the rest of the bunch were all up and running at the time.
After I found out and the machine was up, I tried to start the demo database that was just installed (8.1.6). Svrmgrl, connect internal, startup. I figured if anything happened in the reboot it would let me know after trying to start it up. I get a "not connected to oracle" error. I try to log in, it says a startup/shutdown is in progress. I try to shut it down, and it gives me a "not connected to oracle" no matter what I do.
I start checking the Alert logs, there are a bunch of these:
Errors in file /app/oralmc/demodb/8.1.6/admin/udump/demo_ora_8359.trc:
ORA-07445: exception encountered: core dump [lxdgetobj()+60] [SIGSEGV] [Address
not mapped to object]   
I'm assuming there isn't much I can do other than Open a TAR and hope I can get it open, or re-install (it's the vision demo database installed with applications). I don't have a backup yet because I just installed it yesterday, and didn't have the disk space to temporarily store the files I needed, or have the sysadmin available to dump it to tape.
It's not a huge loss, it's just the canned demo database anyway, just a pain how things tend to work out.