In the same vein as the "what got you into computers" thread, I thought I'd start this one.  I'm sure those of us who work on computers day after day have stories of the strange and unusual.  To kick it off, I'll give my odd tale.
 
This was about 3 years ago when I worked in my cities IT dept.  They had me upgrading peoples computers.  They needed to use USB devices, and most of the machines ran NT4.0.  For those that don't know, NT doesn't handle USB, so I was slowly upgrading machines to windows 2000.  (yes, I said three years ago, don't ask why we weren't upgrading to XP.)  I had a computer on the test bed and had finished loading the image onto it.  My next task was to update windows for any patches not on the image, and to install/tweak a few programs.  (these machines all took the same image, but depending on the dept needed more things.)  It was after I was rebooting that the machine found a virus.  
 
Frankly, this should have been impossible.  All computers used AV, and the only place this machine went on the internet was to MS update site.  So, the question became, where did this virus come from?  Alerting the network manager, he "talked" to the switches, and found us an IP address that was listening on ports that it shouldn't.  The problem was, their IP address log wasn't up to date, and they had no idea where the offending computer was.  (updating the IP logs was my other task.  Not fun I assure you.)  All of this happened on a friday, so I spent much of my weekend thinking about this.
 
The "computer" was found by somebody over the weekend.  It was a plotter on the second floor of the building, in the engineering section.  (a plotter is similar to a giant printer.)  No body ever realized that there was an OS underneath the plotters basic menu screen.  The plotter ran on windows 2000, and because nobody know, it had never been patched.  Or virus scanned.  I have no idea how they fixed it, I was sent back to my lair to image computers...
 
Anyone else have stories of the "strange and unusual"?

Interesting story.  That plotter machine must have been infested with crud lol.  The strangest computer related story I got was the time I tried changing my ram timings from 5-5-5-15 to 4-4-4-12 at stock ddr2 800 speeds, my system hanging and then being really unstable at anything above a small cpu oc from the stock speeds after being stable at twice the oc for months and months.  Long story short, before ordering a new mobo in desperation at it all, I tried a bios update.  Well I be damned, it did the trick.  Old memory works fine by the way, nothing broke at all.  Quite an odd experience all round really.  

 
This is actually very common. Networked multifunction copiers are the same way (some even run Win2K as well) and people are just now starting to become aware of the potential security problems they can cause.  

My wonderful story:
Nvidia FX5900, 4 Harddrives, 2 memsticks, 2 USB Devices, 2 PCI Cards,
Pentium IV @ 2.8ghz. ran (STABLE!!!) on a 250w PSU for over a year.
 
The thing was that i loaned out my 350w PSU to a friend and took one
of my older random PSUs, which i didnt remember until one year later.
 
that 250w PSU must have been made out of diamonds.
its now sitting in a PIII system instead (where it should be), still kicking.

@engineer, the networked copiers was one of our first guesses.  We were reasonably sure it wasn't a PC, as they were all patched and have AV software on them.  It must have been something we missed.
 
@strobe, WOW.  Do you remember the brand of the PSU?  Where did you get it?  Dell "makes" a PSU that is rated at 305W thats pretty solid.  I wonder if it was a much earlier model of that one...

My old Gateway P4 2.0 Ghz computer I put in a 2.6Ghz P4 and tossed in 2 512MB sticks of memory and the Radeon X700 Pro and that ran fine.  Eventually I got nervous and threw in a 430W PSU.
 
The Gateway came with a 165W PSU.  

LOL, I think I've seen those.  They are about the size of two decks of cards.  I remember seeing one for the first time and thinking how did they get all the PSU stuff in there????  I'm surprised you got a 430W to fit in there, I thought the mounting holes were non standard.

Strobe, we used to run servers on PSUs from Sparkle Power Inc (aka SPI).  300W ran 2 P3s, a server class mobo with two onboard scsi channels, 3 scsi 10k drives, an optical, a RAID controller, and multiple NICs.  I've always said SPI makes good, cheap PSUs.  Not pretty, but powerful.  You can tell it was decent quality because it weighed like 3 or 4 pounds.

The PSU says "FSG Group" on the sidelabel.
its old as hell, ive used it for my first system ever which was an K6-2 500mhz
 
but, up to date now it has retired TODAY. the p3 system eventually started to have spontaenous reboot problem under 100% CPU load.
 
so i guess the PSU did take some damage under my abusing in the P4 system.

Perhaps, don't forget to check the motherboard.  Motherboards from that era can develop capacitor problems.  

hehehe, the capacitors does have a small budgin on them, but they have been in the same state for the last 3 years , and switching the PSU did help! =D
 
so, the capacitors on the mobo is not top notch but still holding

My weird story was just happened a few weeks ago with my customer computer. It's Intel P4 2.4 Ghz, Mobo Intel 865, DDR 512Mb PC2700, HDD Seagate 80Gb, Generic 350 Watt PSU and Winfast 7300LE 256Mb PCI-E that has run fine for at least 6 months before and suddenly cannot booting.  
 
When I power on the system, all the fans was running but the monitor has no display, the led from the monitor just keep blinking red and green, no beeping sound either from the BIOS.
 
First, I think the VGA went dead but to make sure, I plug it in another computer but it works normally. Second guess is the mobo, but the onboard video and cpu work just fine. So, the third guess is the mobo PCI-E slot itself but to make sure I replaced it with another brand new 7200GS 256mb but it also work normally. And then I returned the 7300LE again to the mobo, it still cannot boot. Why folks?  
 
Until now, the problem remains unsolved. I just replace his computer with brand new 7200GS.

I work in an IT department at a medium sized healthcare organization. A guy from maintenance calls me up and says "You might want to come take a look at this printer... based on the smell we think something died in it." So I go across the street (thank god this wasn't in the hospital proper) and by the time I get there the guys from maintenance have disassembled an HP Laserjet 4. They've got the doors and windows open trying to air out an AWFUL smell. A mouse had found its way into the power supply of the printer and had been electrocuted to death. When he got zapped he apparently lost control of himself and sprayed feces EVERYWHERE inside the power supply. It was truly disgusting. We retired that printer that day.

^ROFL^

 
   
 
That one wins in my book...

Damn!! Talk about "bugs" in the printer!!!

oh man that rat one was a good way to start my day.

Awww... thanks guys.

+1
Absolutely classic.

Hi, Long time ago I work for a small pharmaceutical company. At that time the company have only 5 pc's and all the other screen are Wyse terminal connect to a database for order and everything. when we decide to go for pc's we bought 5 tets pc's , load and configure them, check network card, patch, application compatibilty everything looks find.  
so we ask the dealer to send us the other 120 pc's we need, the only restriction we have is, all of those pc's does have the exact same harware configuration, we are clear on that. We received the 120 pc's and hell start. not even the image we made will boot the new pc's. Only 40 will work with the image , we call back the company and tell to the salesman "your pc's are not compliant on what we need please take them back". At that moments I think the guy will start to cry over the phone. We find out a solution, he send to us 20 of his tech to load all of the pc's during the weekend. Too install everything. when everything is done one of thech said to me.  
 
"you have three version of your network card, same number, same specification, different version number and you have 2 different version of the same motherboard, and the viedo driver needed are not exactly the same, you need 3 of them". After that when we have a problem with a pc's you should see the amount cd,floopy we need to be prepare for maintenance.  
 
That's my nightmare , but since that time when I have to bought large number of pc's they always be loaded and fully functionnal before leaving the warehouse.